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Diagnostic Trouble Codes

DTC
Description
B0163
In-car Sensor Input voltage short to ground or open
B0173
Duct Temperature Sensor input voltage short to battery or open
B0183
Sun Sensor short to battery or open
B0193
Power Module (Blower Motor Speed) short to battery or open
B0228
Air Intake Motor Feedback voltage short to battery or open
B0283
Electric Rear Defrost short to battery or open
B0413
Air Mix Door Motor Feedback voltage short to battery or open
B1000
ROM,or Calibration Memory Failure
B3779
Mode Door Motor Feedback voltage short to battery or open
B3843
Anti-Pollution Sensor input voltage short to battery or open
B3933
Air Conditioning Evaporator Temperature Sensor input voltage short to ground or open
U0020
Low Speed CAN Communication Bus Performance
U0073
Control Module Communication Bus Off
U0140
Lost Communications with Body Control Module (BCM)
U0155
Lost Communications with Instrument Panel Cluster (IPC)

Trouble Code Diagnosis DTC B0163

DTC Descriptor

This diagnostic procedure supports the following DTC

Circuit Description

In-car sensor or Front PCAT Sensor allow the HVAC control module to monitor the temperature of the in the car.

Conditions for Running the DTC

Ignition is ON.

Conditions for Setting the DTC

Action Taken When the DTC Sets

The In-car sensor or PCAT sensor value setting in 25°.

Conditions for Clearing the DTC

Diagnostic Aids

The numbers below refer to the step numbers on the diagnostic table.
  1. Tests resistance of the In-car sensor or PCAT sensor (2.2KΩ in 25°C).
  2. Tests the voltage of the In-car sensor or PCAT sensor from the HVAC control module (2.2V in 25°C)
StepActionValue(s)YesNo
1
Did you perform the Diagnostic System Check - Vehicle?
-
Go to Step 2
Go to Diagnostic System Check - Vehicle
2
  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. With a scan tool, observe the In-car sensor value in the Heating and Air Conditioning data list.
Does the scan tool indicate that the In-car parameter is within the specified range?
0.27~4.64V
Go to Step 8
Go to Step 3
3
  1. Turn OFF the ignition.
  2. Disconnect the In-car sensor.
  3. Turn ON the ignition, with the engine OFF.
  4. With a scan tool, observe the In-car sensor data parameter.
Does the scan tool indicate that the In-car data parameter is greater than the specified value?
4.64V
Go to Step 4
Go to Step 5
4
  1. Turn OFF the ignition.
  2. Connect a fused jumper wire between the signal circuit of the In-car sensor and the low reference circuit of the In-car sensor.
  3. Turn ON the ignition, with the engine OFF.
  4. With a scan tool, observe the In-car sensor parameter.
Does the scan tool indicate that the Duct Actual data parameter is less than the specified value?
0.27V
Go to Step 8
Go to Step 6
5
Test the signal circuit of the In-car sensor for a short to ground.
Did you find and correct the condition?
-
Go to Step 12
Go to Step 9
6
Test the signal circuit of the In-car sensor for a short to voltage, a high resistance, or an open.
Did you find and correct the condition?
-
Go to Step 12
Go to Step 7
7
Test the low reference circuit of the In-car sensor for a high resistance or an open.
Did you find and correct the condition?
-
Go to Step 12
Go to Step 9
8
Inspect for poor connections at the harness connector of the In-car sensor.
Did you find and correct the condition?
-
Go to Step 12
Go to Step 10
9
Inspect for poor connections at the harness connector of the HVAC control module.
Did you find and correct the condition?
-
Go to Step 12
Go to Step 11
10
Replace the In-car sensor.
Did you complete the replacement?
-
Go to Step 12
-
11
Replace the HVAC control module.
Did you complete the replacement?
-
Go to Step 12
-
12
  1. Use the scan tool in order to clear the DTCs.
  2. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.
Does the DTC reset?
-
Go to Step 2
System OK

Trouble Code Diagnosis DTC B0173

DTC Descriptor

This diagnostic procedure supports the following DTC

Circuit Description

Front Duct Sensor allow the HVAC control module to monitor the temperature of the in the car.

Conditions for Running the DTC

Ignition is ON.

Conditions for Setting the DTC

Action Taken When the DTC Sets

The Duct Sensor value setting in 75°.

Conditions for Clearing the DTC

Test Description

The numbers below refer to the step numbers on the diagnostic table.
  1. Tests the voltage of the Duct Sensor (2.2V in 25°C).
  2. Tests resistance of the Duct Sensor (2.2KΩ in 25°C)
StepActionValue(s)YesNo
1
Did you perform the Diagnostic System Check - Vehicle?
-
Go to Step 2
Go to Diagnostic System Check - Vehicle
2
  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. With a scan tool, observe the Duct Sensor value in the Heating and Air Conditioning data list.
Does the scan tool indicate that the duct sensor value is within the specified range?
0.27~4.64V
Go to Step 8
Go to Step 3
3
  1. Turn OFF the ignition.
  2. Disconnect the Duct Sensor.
  3. Turn ON the ignition, with the engine OFF.
  4. With a scan tool, observe the Duct Sensor data parameter.
Does the scan tool indicate that the duct sensor value is greater than the specified value?
4.64V
Go to Step 4
Go to Step 5
4
  1. Turn OFF the ignition.
  2. Connect a fused jumper wire between the signal circuit of the Duct Sensor and the low reference circuit of the Duct Sensor.
  3. Turn ON the ignition, with the engine OFF.
  4. With a scan tool, observe the Duct Sensor parameter.
Does the scan tool indicate that the Duct sensor value is less than the specified value?
0.27V
Go to Step 8
Go to Step 6
5
Test the appropriate signal circuit of the Duct Sensor for a short to ground.
Did you find and correct the condition?
-
Go to Step 12
Go to Step 9
6
Test the signal circuit of the duct sensor for a short to voltage, a high resistance, or an open.
Did you find and correct the condition?
2.2V
Go to Step 12
Go to Step 7
7
Test the reference circuit of the duct sensor.
Does the scan tool indicate that the duct sensor value is within the specified range?
2.2KΩ
Go to Step 12
Go to Step 9
8
Inspect for poor connections at the harness connector of the duct sensor.
Did you find and correct the condition?
-
Go to Step 12
Go to Step 10
9
Inspect for poor connections at the harness connector of the HVAC control module.
Did you find and correct the condition?
-
Go to Step 12
Go to Step 11
10
Replace the Duct Sensor.
Did you complete the replacement?
-
Go to Step 12
-
11
Replace the HVAC control module.
Did you complete the replacement?
-
Go to Step 12
-
12
  1. Use the scan tool in order to clear the DTCs.
  2. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.
Does the DTC reset?
-
Go to Step 2
System OK

Trouble Code Diagnosis DTC B0183

DTC Descriptor

This diagnostic procedure supports the following DTC

Circuit Description

The front left solar sensor provide the HVAC control module with inputs as to the amount heat load the sun is placing on the interior of the vehicle. The solar sensor are photodiodes that are sensitive to light intensity. The HVAC control module applies 5 volts to internal input resistors that are connected to the front left signal circuits of the solar sensor. The HVAC control module provides ground to the sensors through the low reference circuit. The HVAC control module monitors the voltage drops across the solar sensor and converts the voltage values to count values where 1 volt is approximately equal to 51 counts. As the light intensity increases, the sun sensors allow more current to travel through the circuits and the signal voltages decrease. As the light intensity decreases, the solar sensor allow less current to travel through the circuits and the signal voltages increase.

Conditions for Running the DTC

Ignition is ON.

Conditions for Setting the DTC

Action Taken When the DTC Sets

The Duct Sensor value setting in 0.

Conditions for Clearing the DTC

Test Description

The numbers below refer to the step numbers on the diagnostic table.
  1. Tests current of the HVAC control module terminal. (Under the direct rays of the sun : 3.2V or under the place in the shade : 4.0V)
StepActionValue(s)YesNo
1
Did you perform the Diagnostic System Check - Vehicle?
-
Go to Step 2
Go to Diagnostic System Check - Vehicle
2
  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. With a scan tool, observe the Solar Sensor parameter in the body control module (BCM) data list.
Does the scan tool indicate that the Solar Sensor parameter is within the specified range?
0.27~4.64V
Go to Step 8
Go to Step 3
3
  1. Turn OFF the ignition.
  2. Disconnect the solar sensor assembly.
  3. Turn ON the ignition, with the engine OFF.
  4. With a scan tool, observe the appropriate Solar Sensor data parameter.
Does the scan tool indicate that the appropriate Solar Sensor parameter is greater than the specified value?
4.64V
Go to Step 4
Go to Step 5
4
  1. Turn OFF the ignition.
  2. Connect a fused jumper wire between the signal circuit of the solar sensor assembly and the low reference circuit of the solar sensor assembly.
  3. Turn ON the ignition, with the engine OFF.
  4. With a scan tool, observe the appropriate Solar Sensor parameter.
Does the scan tool indicate that the Solar Sensor parameter is less than the specified value?
0.20V
Go to Step 8
Go to Step 6
5
Test the appropriate solar signal circuit of the solar sensor assembly for a short to ground.
Did you find and correct the condition?
-
Go to Step 12
Go to Step 9
6
Test the appropriate signal circuit of the solar sensor assembly for a short to voltage, a high resistance, or an open.
Did you find and correct the condition?
2.2V
Go to Step 12
Go to Step 7
7
Test the low reference circuit of the solar sensor assembly for a high resistance or an open.
Did you find and correct the condition?
-
Go to Step 12
Go to Step 9
8
Inspect for poor connections at the harness connector of the solar sensor assembly.
Did you find and correct the condition?
-
Go to Step 12
Go to Step 10
9
Inspect for poor connections at the harness connector of the HVAC module.
Did you find and correct the condition?
3.2~4.0V
Go to Step 12
Go to Step 11
10
Replace the solar sensor assembly.
Did you complete the replacement?
-
Go to Step 12
-
11
Replace the HVAC control module. Refer to for replacement, setup, and programming.
Did you complete the replacement?
-
Go to Step 12
-
12
  1. Use the scan tool in order to clear the DTCs.
  2. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.
Does the DTC reset?
-
Go to Step 2
System OK

Trouble Code Diagnosis DTC B0193

DTC Descriptor

This diagnostic procedure supports the following DTC

Circuit Description

Power Transistor is to control blower motor and input the signal into a HVAC control module.

Conditions for Running the DTC

Ignition is ON.

Conditions for Setting the DTC

Action Taken When the DTC Sets

The In-car sensor value setting in 25°

Conditions for Clearing the DTC

Test Description

The numbers below refer to the step numbers on the diagnostic table.
  1. Tests voltage of the blower motor level between low and high level and increase the voltage all level at 0.5V.
Level
0
1
2
3
4
5
6
7
V
0
4.0
4.5
5.0
5.5
6.0
6.5
7.0
Level
8
9
10
11
12
13
14
15
V
7.5
8.0
8.5
9.0
9.5
10.0
10.5
Max
StepActionValue(s)YesNo
1
Did you perform the Diagnostic System Check - Vehicle?
-
Go to Step 2
Go to Diagnostic System Check - Vehicle
2
Test the appropriate power transistor Assembly signal circuit of the power transistor Assembly for a short to ground.
Did you find and correct the condition?
-
Go to Step 8
Go to Step 3
3
Test the appropriate signal circuit of the power transistor Assembly for a short to voltage, a high resistance, or an open.
Did you find and correct the condition?
-
Go to Step 8
Go to Step 4
4
Test the voltage the power transistor and change each level.
Did you find and correct the condition?
-
Go to Step 8
Go to Step 5
5
Inspect for poor connections at the harness connector of the power transistor Assembly.
Did you find and correct the condition?
-
Go to Step 8
Go to Step 5
6
Inspect for poor connections at the harness connector of the HVAC module.
Did you find and correct the condition?
5.0V
Go to Step 8
Go to Step 7
7
Replace the power transistor Assembly.
Did you complete the replacement?
-
Go to Step 8
-
8
  1. Use the scan tool in order to clear the DTCs.
  2. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.
Does the DTC reset?
-
Go to Step 2
System OK

Trouble Code Diagnosis DTC B0228

DTC Descriptor

The following DTCs are for the HVAC door actuators :

Circuit Description

The HVAC control module controls the HVAC door actuators to regulate the airflow through the HVAC system. Each actuator consists of a stepper motor, a logic circuit, and a potentiometer. The potentiometer inside the door actuator allows the module to monitor the current position of the actuator drive shaft. The module supplies a 5-volt source voltage to the potentiometer on the 5-volt reference circuit. The module supplies ground to the potentiometer through the low reference circuit. The HVAC control module monitors the voltage drop across the potentiometer on the door position signal circuit. When the actuator shaft rotates, the voltage on the door position signal circuit changes. The HVAC control module calibrates the travel range of the HVAC door actuators when it is initially powered by the battery positive voltage circuit. During calibration, the module commands the actuators in each direction until door travel is stopped. The module stores the minimum door positions and the maximum door positions of each actuator into memory. The total travel range is calculated by subtracting the minimum door position from the maximum door position. The door actuators can be calibrated again with a scan tool.

Conditions for Running the DTC

Conditions for Setting the DTC

The DTC sets when one of the following conditions are present :

Conditions for Clearing the DTC

Diagnostic Aids

  1. Ignition switch ON
  2. Check the ignition voltage (12V) and motor voltage (5V) of air intake door motor.
  3. Check the reference of air intake door motor.
AMD
Mode
Reference
Cool
P1(-), P2(+)
Under the 1KΩ
Hot
P1(+), P2(-)
Over the 8KΩ
StepActionValue(s)YesNo
1
Did you perform the Diagnostic System Check - Vehicle?
-
Go to Step 2
Go to Diagnostic System Check - Vehicle in Vehicle DTC Information
2
Is DTC B0228 set as a current DTC?
-
Go to Diagnostic Trouble Code (DTC) List - Vehicle in Vehicle DTC Information
Go to Step 3
3
With a scan tool, observe the Heating and Air Conditioning DTC list.
Does the scan tool indicate that at least 2 of the following DTCs B0413 and B3779 are set as current DTC?
-
Go to Step 6
Go to Step 4
4
  1. Disconnect the fused jumper.
  2. Measure the voltage between the 5-volt reference circuit and the low reference circuit of the HVAC door actuator.
Does the voltage measure less than the specified value?
5.5V
Go to Step 5
Go to Step 10
5
  1. Turn OFF the ignition.
  2. Disconnect the negative battery cable.
  3. Measure the resistance from the low reference circuit of the HVAC door actuator to a good ground.
Does the resistance measure less than the specified value?
5 ohms
Go to Step 11
Go to Step 13
6
  1. Disconnect the most accessible affected HVAC door actuator.
  2. Probe the low reference circuit of the HVAC door actuator with a test lamp from battery positive voltage.
Does the test lamp illuminate?
-
Go to Step 78
Go to Step 14
7
  1. Turn ON the ignition, with the engine OFF.
  2. With a scan tool, observe the Heating and Air Conditioning DTC list.
  3. While observing DTC list, disconnect and connect the electrical connector for each affected HVAC door actuator.
Did the scan tool indicate that only one DTC was present when a HVAC door actuator was disconnected?
-
Go to Step 9
Go to Step 8
8
Test the 5-volt reference circuit of the appropriate HVAC door actuator for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
-
Go to Step 19
Go to Step 16
9
Test the appropriate door position signal circuit of the HVAC door actuator for a short to ground.
Did you find and correct the condition?
-
Go to Step 19
Go to Step 15
10
Test the 5-volt reference circuit of the appropriate HVAC door actuator for a short to voltage.
Did you find and correct the condition?
-
Go to Step 19
Go to Step 16
11
Test the 5-volt reference circuit of the appropriate HVAC door actuator for a short to ground, for a high resistance, or for an open.
Did you find and correct the condition?
-
Go to Step 19
Go to Step 12
12
Test the appropriate door position signal circuit of the HVAC door actuator for a short to ground, for a high resistance, or for an open.
Did you find and correct the condition?
-
Go to Step 19
Go to Step 16
13
Test the appropriate door position signal circuit of the HVAC door actuator for a short to voltage.
Did you find and correct the condition?
-
Go to Step 19
Go to Step 16
14
  1. Disconnect the HVAC control module.
  2. Test the low reference circuit of the appropriate HVAC door actuator for a high resistance or for an open.
Did you find and correct the condition?
-
Go to Step 19
Go to Step 16
15
Inspect for poor connections at the harness connector of the appropriate HVAC door actuator.
Did you find and correct the condition?
-
Go to Step 19
Go to Step 17
16
Inspect for poor connections at the harness connector of the HVAC control module.
Did you find and correct the condition?
-
Go to Step 19
Go to Step 18
17

Important : Perform the calibration procedure for HVAC door actuators.

Replace the HVAC door actuator.
Did you complete the replacement?
-
Go to Step 19
-
18
Replace the HVAC control module. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.
Did you complete the replacement?
-
Go to Step 19
-
19
  1. Use the scan tool in order to clear the DTCs.
  2. Operate the vehicle according to the Conditions for Running in the DTC as specified in the supporting text.
Does the DTC set again?
-
Go to Step 4
System OK

Trouble Code Diagnosis DTC B0283

DTC Descriptor

This diagnostic procedure supports the following DTC :

Circuit Description

The Body Control Module(BCM) controls the DEFOG relay circuit. When the ignition switch is in Run position and the operator has depressed the defogger switch, the Body Control Module(BCM) provides power to the DEFOG relay control circuit.

Conditions for Running the DTC

The system voltage must be between 9-16 volts.

Conditions for Setting the DTC

The Body Control Module(BCM) detects a short to battery positive voltage in the DEFOG relay control circuit when the Body Control Module(BCM) is trying to energize the relay.
The Body Control Module(BCM) detects that the DEFOG relay control circuit is open.
The condition above must be present for more than 1 second.

Action Taken When the DTC Sets

Conditions for Clearing the DTC

Test Description

The numbers below refer to the step numbers on the diagnostic table.
  1. Tests for battery positive voltage at the coil side of the dear window defogger relay. The EF25 (10A) fuse supplies power to the coil side of the DEFOG relay.
  2. Tests the control circuit side of the DEFOG relay for faults that cause DTC B0283.
  3. Listen for an audible click when the DEFOG relay operates. Command both the ON and OFF states. Repeat the commands as necessary.
  4. Verifies that the Body Control Module(BCM) is providing ground to the DEFOG relay.
StepActionValue(s)YesNo
1
Did you perform the Diagnostic System Check - Vehicle?
-
Go to Step 2
Go to Diagnostic System Check - Vehicle in Vehicle DTC Information
2
  1. Remove the DEFOG relay
  2. Connect a test lamp between the DEFOG relay Ef25(10A) fused voltage supply circuit and ground at the DEFOG relay socket.
  3. Turn ON the ignition, with the engine OFF.
Does the test lamp illuminate?
-
Go to Step 3
Go to Step 8
3
  1. Turn OFF the ignition.
  2. Test the control circuit of the DEFOG relay for a short to battery positive voltage and ground.
Did you find and correct the condition?
-
Go to Step 11
Go to Step 4
4
  1. Connect a test lamp between the Ef25 (10A) fused voltage supply circuit and the control circuit of the DEFOG relay socket.
  2. Turn ON the ignition, with the engine OFF.
  3. Using a scan tool, command the relay ON then OFF.
Does the test lamp turn ON and OFF?
-
Go to Step 6
Go to Step 5
5
Test the control circuit of the DEFOG relay for an open.
Did you find and correct the condition?
-
Go to Step 11
Go to Step 7
6
Inspect for poor connections and terminal damage at the relay socket.
Did you find and correct the condition?
-
Go to Step 11
Go to Step 9
7
Inspect for poor connections at the harness connector of the body control module (BCM).
Did you find and correct the condition?
-
Go to Step 11
Go to Step 10
8
Repair the short to ground, poor connection or an open in the EF25(10A) fused voltage supply circuit.
Did you complete the repair?
-
Go to Step 11
-
9
Replace the DEFOG relay.
Did you complete the replacement?
-
Go to Step 11
-
10
Replace the Body Control Module (BCM).
Did you complete the replacement?
-
Go to Step 11
-
11
  1. Use the scan tool in order to clear the DTCs.
  2. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.
Does the DTC reset?
-
Go to Step 2
System OK

Trouble Code Diagnosis DTC B0413

DTC Descriptor

The following DTCs are for the HVAC door actuators :

Circuit Description

The HVAC control module controls the HVAC door actuators to regulate the airflow through the HVAC system. Each actuator consists of a stepper motor, a logic circuit, and a potentiometer. The potentiometer inside the door actuator allows the module to monitor the current position of the actuator drive shaft. The module supplies a 5-volt source voltage to the potentiometer on the 5-volt reference circuit. The module supplies ground to the potentiometer through the low reference circuit. The HVAC control module monitors the voltage drop across the potentiometer on the door position signal circuit. When the actuator shaft rotates, the voltage on the door position signal circuit changes. The HVAC control module calibrates the travel range of the HVAC door actuators when it is initially powered by the battery positive voltage circuit. During calibration, the module commands the actuators in each direction until door travel is stopped. The module stores the minimum door positions and the maximum door positions of each actuator into memory. The total travel range is calculated by subtracting the minimum door position from the maximum door position. The door actuators can be calibrated again with a scan tool.

Conditions for Running the DTC

The ignition is ON.

Conditions for Setting the DTC

The DTC sets when one of the following conditions are present :

Conditions for Clearing the DTC

Diagnostic Aids

  1. Ignition switch ON.
  2. Ignition switch ON.
  3. Check the ignition voltage (12V) and motor voltage (5V) of air intake door motor.
  4. Check the reference of air intake door motor.
AMD
Mode
Reference
Cool
P1(-), P2(+)
Under the 1KΩ
Hot
P1(+), P2(-)
Over the 8KΩ
StepActionValue(s)YesNo
1
Did you perform the Diagnostic System Check - Vehicle?
-
Go to Step 2
Go to Diagnostic System Check - Vehicle in Vehicle DTC Information
2
Is DTC B0413 set as a current DTC?
-
Go to Diagnostic Trouble Code (DTC) List - Vehicle in Vehicle DTC Information
Go to Step 3
3
With a scan tool, observe the Heating and Air Conditioning DTC list.
Does the scan tool indicate that at least 2 of the following DTCs B0228 and B3779 are set as current DTC?
-
Go to Step 6
Go to Step 4
4
  1. Disconnect the fused jumper.
  2. Measure the voltage between the 5-volt reference circuit and the low reference circuit of the HVAC door actuator.
Does the voltage measure less than the specified value?
5.5V
Go to Step 5
Go to Step 10
5
  1. Turn OFF the ignition.
  2. Disconnect the negative battery cable.
  3. Measure the resistance from the low reference circuit of the HVAC door actuator to a good ground.
Does the resistance measure less than the specified value?
5 ohms
Go to Step 11
Go to Step 13
6
  1. Disconnect the most accessible affected HVAC door actuator.
  2. Probe the low reference circuit of the HVAC door actuator with a test lamp from battery positive voltage.
Does the test lamp illuminate?
-
Go to Step 78
Go to Step 14
7
  1. Turn ON the ignition, with the engine OFF.
  2. With a scan tool, observe the Heating and Air Conditioning DTC list.
  3. While observing DTC list, disconnect and connect the electrical connector for each affected HVAC door actuator.
Did the scan tool indicate that only one DTC was present when a HVAC door actuator was disconnected?
-
Go to Step 9
Go to Step 8
8
Test the 5-volt reference circuit of the appropriate HVAC door actuator for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
-
Go to Step 19
Go to Step 16
9
Test the appropriate door position signal circuit of the HVAC door actuator for a short to ground.
Did you find and correct the condition?
-
Go to Step 19
Go to Step 15
10
Test the 5-volt reference circuit of the appropriate HVAC door actuator for a short to voltage.
Did you find and correct the condition?
-
Go to Step 19
Go to Step 16
11
Test the 5-volt reference circuit of the appropriate HVAC door actuator for a short to ground, for a high resistance, or for an open.
Did you find and correct the condition?
-
Go to Step 19
Go to Step 12
12
Test the appropriate door position signal circuit of the HVAC door actuator for a short to ground, for a high resistance, or for an open.
Did you find and correct the condition?
-
Go to Step 19
Go to Step 16
13
Test the appropriate door position signal circuit of the HVAC door actuator for a short to voltage.
Did you find and correct the condition?
-
Go to Step 19
Go to Step 16
14
  1. Disconnect the HVAC control module.
  2. Test the low reference circuit of the appropriate HVAC door actuator for a high resistance or for an open.
Did you find and correct the condition?
-
Go to Step 19
Go to Step 16
15
Inspect for poor connections at the harness connector of the appropriate HVAC door actuator.
Did you find and correct the condition?
-
Go to Step 19
Go to Step 17
16
Inspect for poor connections at the harness connector of the HVAC control module.
Did you find and correct the condition?
-
Go to Step 19
Go to Step 18
17

Important : Perform the calibration procedure for HVAC door actuators.

Replace the HVAC door actuator.
Did you complete the replacement?
-
Go to Step 19
-
18
Replace the HVAC control module. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.
Did you complete the replacement?
-
Go to Step 19
-
19
  1. Use the scan tool in order to clear the DTCs.
  2. Operate the vehicle according to the Conditions for Running in the DTC as specified in the supporting text.
Does the DTC set again?
-
Go to Step 4
System OK

Trouble Code Diagnosis DTC B1000

Circuit Description

This diagnostic applies to internal microprocessor integrityconditions within the HVAC control module.

Conditions for Running the DTC

Conditions for Setting the DTC

Action Taken When the DTC Sets

Conditions for Clearing the DTC

StepActionValue(s)YesNo
1
Perform the Diagnostic System Check. Is the system check complete?
-
Go to Step 2
Go to Diagnostic System Check - Vehicle
2
  1. Turn the ignition switch to LOCK.
  2. Install a scan tool to the data link connector (DLC).
  3. Turn the ignition switch to ON.
  4. Observe DTC information with a scan tool.
Did the DTC fail this ignition?
-
Go to Step 3
Go to Step 4
3
Replace the HVAC control module.
Is the replace complete?
-
Go to Step 4
-
4
  1. Clear the DTCs with a scan tool.
  2. Turn OFF the ignition for 30 seconds.
  3. Ignition switch ON.
Did the DTC fail this ignition?
-
Go to Step 2
Go to Step 5
5
Check if any additional DTCs are set.
Are any DTCs displayed that have not been diag-nosed?
-
Go to applicable DTC table
System OK

Trouble Code Diagnosis DTC B3779

DTC Descriptor

The following DTCs are for the HVAC door actuators :

Circuit Description

The HVAC control module controls the HVAC door actuators to regulate the airflow through the HVAC system. Each actuator consists of a stepper motor, a logic circuit, and a potentiometer. The potentiometer inside the door actuator allows the module to monitor the current position of the actuator drive shaft. The module supplies a 5-volt source voltage to the potentiometer on the 5-volt reference circuit. The module supplies ground to the potentiometer through the low reference circuit. The HVAC control module monitors the voltage drop across the potentiometer on the door position signal circuit. When the actuator shaft rotates, the voltage on the door position signal circuit changes. The HVAC control module calibrates the travel range of the HVAC door actuators when it is initially powered by the battery positive voltage circuit. During calibration, the module commands the actuators in each direction until door travel is stopped. The module stores the minimum door positions and the maximum door positions of each actuator into memory. The total travel range is calculated by subtracting the minimum door position from the maximum door position. The door actuators can be calibrated again with a scan tool.

Conditions for Running the DTC

The ignition is ON.

Conditions for Setting the DTC

The DTC sets when one of the following conditions are present :

Conditions for Clearing the DTC

Diagnostic Aids

  1. Ignition switch ON.
  2. Ignition switch ON.
  3. Check the ignition voltage (12V) and motor voltage (5V) of air intake door motor.
  4. Check the reference of air intake door motor.
AMD
Mode
Reference
Cool
P1(-), P2(+)
Under the 1KΩ
Hot
P1(+), P2(-)
Over the 8KΩ
StepActionValue(s)YesNo
1
Did you perform the Diagnostic System Check - Vehicle?
-
Go to Step 2
Go to Diagnostic System Check - Vehicle in Vehicle DTC Information
2
Is DTC B3779 set as a current DTC?
-
Go to Diagnostic Trouble Code (DTC) List - Vehicle in Vehicle DTC Information
Go to Step 3
3
With a scan tool, observe the Heating and Air Conditioning DTC list.
Does the scan tool indicate that at least 2 of the following DTCs B0228 and B0413 are set as current DTC?
-
Go to Step 6
Go to Step 4
4
  1. Disconnect the fused jumper.
  2. Measure the voltage between the 5-volt reference circuit and the low reference circuit of the HVAC door actuator.
Does the voltage measure less than the specified value?
5.5V
Go to Step 5
Go to Step 10
5
  1. Turn OFF the ignition.
  2. Disconnect the negative battery cable.
  3. Measure the resistance from the low reference circuit of the HVAC door actuator to a good ground.
Does the resistance measure less than the specified value?
5 ohms
Go to Step 11
Go to Step 13
6
  1. Disconnect the most accessible affected HVAC door actuator.
  2. Probe the low reference circuit of the HVAC door actuator with a test lamp from battery positive voltage.
Does the test lamp illuminate?
-
Go to Step 78
Go to Step 14
7
  1. Turn ON the ignition, with the engine OFF.
  2. With a scan tool, observe the Heating and Air Conditioning DTC list.
  3. While observing DTC list, disconnect and connect the electrical connector for each affected HVAC door actuator.
Did the scan tool indicate that only one DTC was present when a HVAC door actuator was disconnected?
-
Go to Step 9
Go to Step 8
8
Test the 5-volt reference circuit of the appropriate HVAC door actuator for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
-
Go to Step 19
Go to Step 16
9
Test the appropriate door position signal circuit of the HVAC door actuator for a short to ground.
Did you find and correct the condition?
-
Go to Step 19
Go to Step 15
10
Test the 5-volt reference circuit of the appropriate HVAC door actuator for a short to voltage.
Did you find and correct the condition?
-
Go to Step 19
Go to Step 16
11
Test the 5-volt reference circuit of the appropriate HVAC door actuator for a short to ground, for a high resistance, or for an open.
Did you find and correct the condition?
-
Go to Step 19
Go to Step 12
12
Test the appropriate door position signal circuit of the HVAC door actuator for a short to ground, for a high resistance, or for an open.
Did you find and correct the condition?
-
Go to Step 19
Go to Step 16
13
Test the appropriate door position signal circuit of the HVAC door actuator for a short to voltage.
Did you find and correct the condition?
-
Go to Step 19
Go to Step 16
14
  1. Disconnect the HVAC control module.
  2. Test the low reference circuit of the appropriate HVAC door actuator for a high resistance or for an open.
Did you find and correct the condition?
-
Go to Step 19
Go to Step 16
15
Inspect for poor connections at the harness connector of the appropriate HVAC door actuator.
Did you find and correct the condition?
-
Go to Step 19
Go to Step 17
16
Inspect for poor connections at the harness connector of the HVAC control module.
Did you find and correct the condition?
-
Go to Step 19
Go to Step 18
17

Important : Perform the calibration procedure for HVAC door actuators.

Replace the HVAC door actuator.
Did you complete the replacement?
-
Go to Step 19
-
18
Replace the HVAC control module. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.
Did you complete the replacement?
-
Go to Step 19
-
19
  1. Use the scan tool in order to clear the DTCs.
  2. Operate the vehicle according to the Conditions for Running in the DTC as specified in the supporting text.
Does the DTC set again?
-
Go to Step 4
System OK

Trouble Code Diagnosis DTC B3843

DTC Descriptor

This diagnostic procedure supports the following DTC :

Circuit Description

HVAC control module detects exhaust gas by Anti Pollution Sensor(APS).

Conditions for Running the DTC

Conditions for Setting the DTC

Action Taken When the DTC Sets

Conditions for Clearing the DTC

Diagnostic Aids

The numbers below refer to the step numbers on the diagnostic table.
  1. Tests voltage of the APS. (Range is 0 to 5V)
  2. Ignition switch is ON and Tests voltage of the HVAC control module connector terminal A16 and A9.
StepActionValue(s)YesNo
1
Did you perform the Diagnostic System Check - Vehicle?
-
Go to Step 2
Go to Diagnostic System Check - Vehicle
2
  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. With a scan tool, observe the APS value in the Heating and Air Conditioning data list.
Does the scan tool indicate that the power transistor Assembly parameter is within the specified range?
0.05~5.0V
Go to Step 7
Go to Step 3
3
  1. Turn OFF the ignition.
  2. Disconnect the APS.
  3. Turn ON the ignition, with the engine OFF.
  4. With a scan tool, observe the appropriate APS data parameter.
Does the scan tool indicate that the appropriate APS parameter is greater than the specified value?
5.0V
Go to Step 4
Go to Step 5
4
  1. Turn OFF the ignition.
  2. Connect a fused jumper wire between the signal circuit of the APS.
  3. Turn ON the ignition, with the engine OFF.
  4. With a scan tool, observe the appropriate APS.
Does the scan tool indicate that the APS is less than the specified value?
0.05V
Go to Step 7
Go to Step 6
5
Test the appropriate APS signal circuit for a short to ground.
Did you find and correct the condition?
-
Go to Step 10
Go to Step 8
6
Test the low reference circuit of the APS for a high resistance or an open.
Did you find and correct the condition?
-
Go to Step 10
Go to Step 8
7
Inspect for poor connections at the harness connector of the APS.
Did you find and correct the condition?
-
Go to Step 10
Go to Step 9
8
Inspect for poor connections at the harness connector of the HVAC module.
Did you find and correct the condition?
5.0V
Go to Step 10
Go to Step 9
9
Replace the APS.
Did you complete the replacement?
-
Go to Step 10
-
10
  1. Use the scan tool in order to clear the DTCs.
  2. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.
Does the DTC reset?
-
Go to Step 2
System OK

Trouble Code Diagnosis DTC B3933

DTC Descriptor

DTC B3933 : Air Conditioning (A/C) Evaporator Temperature Sensor Circuit Voltage Above Thershold

Circuit Description

The HVAC control module monitors the evaporator temperature via the evaporator temperature sensor. When the air is cold, the sensor resistance and signal voltage are high. When the air is warm, the sensor resistance and signal voltage are low.

Conditions for Running the DTC

Conditions for Setting the DTC

The HVAC control module detects the evaporator temperature sensor signal circuit is less than 0.09 volt (5 counts) or greater than 4.90 volts (250 counts).

Action Taken When the DTC Sets

Conditions for Clearing the DTC

Test Description

The numbers below refer to the step numbers on the diagnostic table.
  1. This step tests for the proper operation of the circuit in the high voltage range.
  2. This step tests for the proper operation of the circuit in the low voltage range. If the fuse in the jumper opens upon performing this test, the signal circuit has a short to voltage.
StepActionValue(s)YesNo
1
Did you perform the Diagnostic System Check - Vehicle?
-
Go to Step 2
Go to Diagnostic System Check - Vehicle
2
  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. With a scan tool, observe the Evaporator Temp parameter.
Does the scan tool indicate that the Evaporator temp parameter is within the specified range?
0.09~4.90V
Go to Step 3
Go to Step 4
3
Check the connection at the Climate Control Panel and replace the terminals if necessary.
Is the repair complete?
-
System OK
Go to Step 4
4
  1. Turn OFF the ignition.
  2. Disconnect the evaporator temperature sensor.
  3. Turn ON the ignition, with the engine OFF.
  4. With a scan tool, observe the Evaporator Temp parameter.
Is the Evaporator Temp parameter greater than the specified value?
4.09V
Go to Step 5
Go to Step 6
5
  1. Turn OFF the ignition.
  2. Connect a 3-amp fused jumper wire between the signal circuit of the evaporator temperature sensor and the low reference circuit of the evaporator temperature sensor.
  3. Turn ON the ignition, with the engine OFF.
  4. With a scan tool, observe the Evaporator Temp parameter.
Is the Evaporator Temp parameter less than the spe-cified value?
0.09V
Go to Step 10
Go to Step 7
6
Test the signal circuit of the evaporator temperature sensor for a short to ground.
Did you find and correct the condition?
-
Go to Step 14
Go to Step 11
7
Test the signal circuit of the evaporator temperature sensor for one of the following conditions :
  • A short to voltage
  • A high resistance
An open Did you find and correct the condition?
-
Go to Step 14
Go to Step 8
8
Test the low reference circuit of the evaporator tem-perature sensor for one of the following conditions :
  • A high resistance
An open Did you find and correct the condition?
-
Go to Step 14
Go to Step 9
9
Test the following signal circuits for a short to voltage :
  • Inside air temperature sensor
  • Ambient air temperature sensor
  • Left sunload sensor
  • Right sunload sensor
  • Ambient light sensor
Did you find and correct the condition?
-
Go to Step 14
Go to Step 11
10
Inspect for poor connections at the harness connector of the evaporator temperature sensor.
Did you find and correct the condition?
-
Go to Step 14
Go to Step 12
11
Inspect for poor connections at the harness connector of the HVAC control module.
Did you find and correct the condition?
-
Go to Step 14
Go to Step 13
12
Replace the evaporator temperature sensor. Refer to Section 7B, Manual Control Heating, Ventilation and Air Conditioning System.
Did you find and correct the condition?
-
Go to Step 14
-
13
Replace the HVAC control module. Refer to Section 7B, Manual Control Heating, Ventilation and Air Conditioning System for replacement, setup, and programming.
Did you complete the replacement?
-
Go to Step 14
-
14
  1. Use the scan tool in order to clear the DTCs.
  2. Operate the vehicle within the Conditions for Running the DTC.
Does the DTC reset?
-
Go to Step 2
System OK

Trouble Code Diagnosis DTC U0020

Diagnostic Fault Information

Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
Circuit
Short to Ground
Open/High Resistance
Short to Voltage
Signal Performance
Low speed GMLAN serial data
1
2¹
-
-
Ground (DLC, terminal 5)
-
1
-
-
¹ An open between the data link connector (DLC) and C 203 will only effect the communication with the scan tool. The vehicle modules will still communicate.
  1. No communication on any low speed GMLAN module.
  2. No communication on a specific low speed GMLAN module

Circuit/System Description

Modules connected to the low speed GMLAN serial data circuit monitor for serial data communications during normal vehicle operation. Operating information and commands are exchanged among the modules when the ignition switch is in any position other than OFF. The low speed GMLAN serial data circuit must be operational for the vehicle to start so the vehicle theft deterrent (VTD) module and body control module (BCM) can communicate. The low speed GMLAN serial data circuit uses SP 203 as the common connection between the modules and the DLC.

Diagnostic Aids

Circuit/System Testing

  1. Test for less than 1 ohm of resistance between the DLC ground circuit terminal 5 and ground.
  2. Ignition OFF, disconnect the harness connector at splice pack SP 300.
  3. Ignition ON, with a scan tool, attempt to communicate with the instrument panel cluster (IPC). Communication should be available.
  4. Install a 3-amp fused jumper wire between pin A and pin M of the splice pack. Install another 3-amp fused jumper wire to pin L.
  5. Using the open end of the jumper wire at pin L, connect to splice pack terminals B through K and attempt to establish communications with each module connected to the splice pack, one at a time. Each module should be able to communicate.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

Trouble Code Diagnosis DTC U0073

DTC Descriptor

DTC U0073 : Control Module Communication Bus Off

Diagnostic Fault Information

Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

Circuit/System Description

The high speed GMLAN serial data circuits are high speed serial data buses used to communicate information between the control modules. Typical data transmission speeds must be high enough to ensure that a required real–time response is maintained. The high speed GMLAN serial data circuits also connect directly to the data link connector (DLC).

Conditions for Running the DTC

  1. Supply voltage to the modules are in the normal operating range.
  2. The vehicle power mode requires serial data communications.

Conditions for Setting the DTC

The module setting the DTC has attempted to establish communications on the GMLAN circuits more than 3 times.

Action Taken When the DTC Sets

Conditions for Clearing the DTC

Diagnostic Aids

Trouble Code Diagnosis DTC U0020 & U0155

DTC Descriptor

DTC U0140 : Lost Communication With Transmission Control Module (TCM)
DTC U0155 :Lost Communication With Instrument Panel Cluster (IPC) Control Module

Diagnostic Fault Information

Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
Circuit
Short to Ground
Open/High Resistance
Short to Voltage
Signal Performance
Low speed GMLAN serial data
1
U0140-U0214
1
-
Battery positive voltage circuits
U0100-U0214
U0100-U0214
-
-
Ignition voltage circuits
U0100-U0214
U0100-U0214
-
-
Module ground circuits
-
U0100-U0214
-
-
Accessory Wakeup Serial Data
U1814
U0100, U0101
-
-
Serial Data Communication Enable
U2099
U0121
-
-
  1. Scan Tool Does Not Communicate with Low Speed GMLAN Device

Circuit/System Description

Modules connected to the high and low speed GMLAN serial data circuits monitor for serial data communications during normal vehicle operation. Operating information and commands are exchanged among the modules. The modules have prerecorded information about what messages are needed to be exchanged on the serial data circuits, for each virtual network. The messages are supervised and also, some periodic messages are used by the receiver module as an availability indication of the transmitter module. Each message contains the identification number of the transmitter module. The body control module (BCM) activates the serial data communication enable and the accessory wakeup serial data circuits by applying voltage when the ignition key is in ACC, ON or START. The serial data communication enable circuit wakes up the electronic brake control module (EBCM) for bus communication and the accessory wakeup serial data circuit wakes up the engine control module (ECM) and transmission control module (TCM).

Conditions for Running the DTC

  1. The system voltage is between 9-16 volts.
  2. The vehicle power mode master requires serial data communication to occur.

Conditions for Setting the DTC

A supervised periodic message that includes the transmitter module availability has not been received.

Action Taken When the DTC Sets

The module(s) is never signaled, therefore the specific subsystem(s) will not function.

Conditions for Clearing the DTC

Diagnostic Aids

Circuit/System Testing

  1. Using the DTC Descriptor and Diagnostic Aids above, determine the module that is not communicating that should be tested.
  2. Ignition OFF, disconnect the harness connector of the module that is not communicating.

Important : Only the high speed GMLAN modules have a the serial data communication enable circuit OR the accessory wakeup serial data circuit. Refer to the module schematics to identify which modules have these circuits. If the module that is not communicating does not have one of these circuits, proceed to step 4.

  1. Ignition ON, verify that a test lamp illuminates between the serial data communication enable circuit OR the accessory wakeup serial data circuit and ground.

Repair Instructions

Perform the Diagnostic Repair Verification after completingthe diagnostic procedure.


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