Trouble Code Diagnosis DTC B2530
DTC Descriptor
DTC B2530 : Front Fog Lamp Control Circuit
Diagnostic Fault Information
Circuit/System Description
Voltage is applied at all times to the fog lamp relay. When the fog lamp switch is placed in the ON position, a ground signal is applied to the body control module (BCM) through the fog lamp switch signal circuit. The BCM then applies a ground to the front fog lamp control circuit. This engages the fog lamp relay and applies voltage through the FOG LAMP fuse to the front fog lamps.
Conditions for Running the DTC
The ignition is ON. Park lamps must be ON and the fog lamps must be commanded ON.
Conditions for Setting the DTC
The BCM detects a short to ground, open, high resistance, or short to voltage on the front fog lamp control circuit.
Action Taken When the DTC Sets
The fog lamps do not illuminate.
Conditions for Clearing the DTC
- The conditions for setting the DTC are no longer present.
- A history DTC clears after 100 malfunction-free ignition cycles.
- The BCM receives the clear code command from the scan tool.
Reference Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
Front Fog Lamp Control Circuit | B2530 | B2530 | B2530 | - |
Circuit/System Verification
Ignition ON, activate the Fog Lamps output control on the scan tool. The Front Fog Lamp Relay Command parameter in the data list should display On and the front fog lamps should illuminate.
Circuit/System Testing
- Ignition OFF, disconnect the I/P fuse block connector J2 and test for a short to voltage, short to ground, an open, or high resistance at terminal 32.
- Ignition ON, activate the Fog Lamps output control on the scan tool and test for a ground signal at the I/P fuse block connector terminal 32.
- If a ground signal is present, replace the engine fuse block. If a ground signal is not present, replace the BCM.
Repair Instructions
Perform the DiagnosticRepair Verificationafter completing the diagnostic procedure.
- I/P FUSE BLOCK Replacement
- ControlModuleReferencesfor BCM replacement and programming
Trouble Code Diagnosis DTC B2545
DTC Descriptor
This diagnostic procedure supports the following DTC :
DTC B2545 Backup Lamps Circuit
Circuit Description
When the body control module (BCM) receives a signal from the TCM indicating the gear selector is in the REVERSE position, the BCM applies battery positive voltage to the backup lamps voltage supply circuit. The backup lamps are grounded at GX401 for the left backup lamp and GX402 for the right backup lamp.
Conditions for Running the DTC
The battery voltage must be between 9-16 volts.
Conditions for Setting the DTC
DTC B2545 is set either when the backup lamps supply voltage circuit is shorted to ground or opened, or if the CHMSL/Backup fused voltage supply circuit to the BCM is shorted to ground or opened.
Action Taken When the DTC Sets
The backup lamps will not operate.
Conditions for Clearing the DTC
- This DTC will clear on current status after the condition for setting the fault is corrected.
- A history DTC will clear after 100 consecutive ignition cycles without a fault present.
- History DTCs can be cleared using a scan tool.
Diagnostic Aids
Perform a visual inspection for loose or poor connections at all related components.
| Step | Action | Value(s) | Yes | No |
| 1 | Did you perform the Diagnostic System Check - Vehicle? | - | Go to Step 2 | |
| 2 | - Install a scan tool.
- Turn the ignition to the ON position, with the engine OFF.
- With a scan tool, select light test and command the backup lamps ON and OFF.
Do the backup lamps turn ON and OFF with each command? | - | Go to Diagnostic Aids | Go to Step 3 |
| 3 | Test the backup lamps voltage supply circuit for a short to ground or an open. Did you find and correct the condition? | - | Go to Step 6 | Go to Step 4 |
| 4 | Test the CHMSL/Backup fused voltage supply circuit to the body control module (BCM) for a short ground or an open. | - | Go to Step 6 | Go to Step 5 |
| 5 | Replace the BCM. Refer to Control Module References for replacement and programming. Did you complete the replacement? | - | Go to Step 6 | - |
| 6 | - Use the scan tool in order to clear the DTCs.
- Operate the vehicle within the Conditions for Running the DTC.
Does the DTC reset? | - | Go to Step 2 | System OK |
Trouble Code Diagnosis DTC B2575
DTC Descriptor
DTC B2575 :Headlamp Control Circuit
Diagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
Headlamp Low relay Control Circuit | B2575 | B2575 | B2575 | - |
Headlamp Low relay Battery Supply Voltage Circuit | B2575 | B2575 | - | - |
Circuit/System Description
The low beam headlamps are controlled by the body control module (BCM). The BCM grounds the headlamp low relay control circuit in order to energize the HEADLAMP LOW relay coil. The HEADLAMP LOW relay then sends voltage to the low beam headlamps.
Conditions for Running the DTC
- The headlamps are commanded ON.
- Headlamp dimmer switch must be in the low beam position.
Conditions for Setting the DTC
One or more of the following conditions are present :
- The headlamp low relay control circuit is open, shorted to ground, or shorted to voltage.
- The headlamp low relay battery supply voltage circuit is open or shorted to ground.
Action Taken When the DTC Sets
The BCM turns off the headlamp low relay control for the remainder of the ignition cycle.
Conditions for Clearing the DTC
- The conditions for setting the DTC are no longer present.
- A history DTC clears after 100 malfunction-free ignition cycles.
- The BCM receives the clear code command from the scan tool.
Circuit/System Verification
Ignition ON, activate the Low Beam output control on the scan tool. The Low relay Command parameter in the data list should display On and the low beam headlamps should illuminate.
Circuit/System Testing
- Ignition OFF, disconnect the engine fuse block connector J2 and test for a short to voltage, short to ground, an open, or high resistance at the connector terminal 26.
- Activate the headlamp switch, place the headlamp dimmer switch in the low beam position, and test for a ground signal at the engine fuse block connector J2 terminal 26.
- If a ground signal is present, replace the engine fuse block. If a ground signal is not present, replace the BCM.
Trouble Code Diagnosis DTC B257A
DTC Descriptor
DTC B257A :Headlamp Switch Input Signal Mismatch
Diagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
Headlamp Switch Off | B257A | B257A | B257A | - |
Park Lamp Switch On | B257A | B257A | B257A | - |
Headlamp Switch On | 1 | 2 | B2575 | - |
Headlamp Ground | - | B257A | 2 | - |
- Headlamps Always On - Low or High Beam
- Headlamps Inoperative - Low Beam
|
Circuit/System Description
When the headlamp switch is in the OFF position, the body control module (BCM) receives a ground signal through the headlamp switch OFF circuit and an open signal on the park lamp ON circuit. When the headlamp switch is in the PARK or HDLP position, the BCM receives an open signal through the headlamp switch OFF circuit and a ground signal through the park lamp ON circuit.
Conditions for Running the DTC
The ignition is ON.
Conditions for Setting the DTC
The BCM receives an unexpected signal along either the headlamp switch OFF circuit or the park lamp ON circuit.
Action Taken When the DTC Sets
The BCM disregards the headlamp switch input and defaults to automatic headlamp function.
Conditions for Clearing the DTC
The BCM clears this code from current when the fault is removed from the system.
Circuit/System Verification
Ignition ON, headlamp switch to PARK, just the park lamps should illuminate.
Circuit/System Testing
- Headlamp switch to OFF, disconnect the BCM connector J6.
- Ignition to ON, connect a test lamp between the headlamp OFF switch circuit and the positive battery terminal. Verify the test lamp illuminates.
- If the test lamp does not illuminate :
Test for a short to voltage or an open in the headlamp OFF switch circuit.
Test for an open in the headlamp ground circuit.
If the circuit/connections test normal replace the headlamp switch.
- Headlamp switch to PARK. Verify the test lamp is not illuminated.
- If the test lamp illuminates, test for a short to ground in the headlamp OFF switch circuit. If the circuit/connections test normal, replace the headlamp switch.
- Headlamp switch to PARK. Connect a test lamp between the park lamp switch ON circuit and the positive battery terminal. Verify the test lamp illuminates.
- If the test lamp does not illuminate, test for a short to voltage or an open in the park lamp switch ON circuit. If the circuit/connections test normal, replace the headlamp switch.
- Headlamp switch to OFF, verify the test lamp does not illuminate.
- If the test lamp does illuminate, test for a short to ground in the park lamp switch ON circuit. If the circuit/connections test normal, replace the headlamp switch.
- If the circuit/connections test normal, replace the BCM.
Repair Instructions
Important : Always perform the Diagnostic Repair Verification after completing the diagnostic procedure.
- Headlamp Switch Replacement
- Control Module References for BCM replacement and programming
Trouble Code Diagnosis DTC B2580
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC B2580 Headlamp High Beam Control Circuit
Circuit Description
When the body control module (BCM) receives a ground signal from the headlamp dimmer switch high beam signal or flash to pass switch signal commanding to illuminate the high beam headlamps, the BCM will energize the high beam relay by grounding the high beam relay control circuit.
Conditions for Running the DTC
The battery voltage must be between 9-16 volts.
Conditions for Setting the DTC
- When the BCM receives a high beam headlamp OFF command and the high beam headlamp relay control circuit is shorted to ground.
- When the BCM receives a high beam headlamp ON command and the high beam headlamp relay control circuit is shorted to voltage or open.
Action Taken When the DTC Sets
The high beam headlamps will not operate or will remain always on.
Conditions for Clearing the MIL/DTC
- This DTC will clear on current status after the condition for setting the fault is corrected.
- A history DTC will clear after 100 consecutive ignition cycles without a fault present.
- History and current DTCs can be cleared using a scan tool.
| Step | Action | Value(s) | Yes | No |
| 1 | Did you perform the Diagnostic System Check - Vehicle? | - | Go to Step 2 | |
| 2 | - Install a scan tool.
- Turn ON the ignition, with the engine OFF.
- With a scan tool, command the high beam relay ON and OFF.
Does the high beam relay turn ON and OFF with each command? | - | Test for Intermittent Conditions and Poor Connections | Go to Step 3 |
| 3 | - Turn OFF the ignition.
- Disconnect the high beam relay.
- Turn ON the ignition, with the engine OFF.
- Probe the battery positive voltage circuit of the high beam relay with a test lamp that is connected to a good ground.
Does the test lamp illuminate? | - | Go to Step 4 | Go to Step 10 |
| 4 | - Connect a test lamp between the control circuit of the high beam relay and the battery positive voltage circuit of the high beam relay.
- With a scan tool, command the high beam relay ON and OFF.
Does the test lamp turn ON and OFF with each command? | - | Go to Step 8 | Go to Step 5 |
| 5 | Does the test lamp remain illuminated with each command? | - | Go to Step 7 | Go to Step 6 |
| 6 | Test the control circuit of the high beam relay for a short to battery positive voltage or an open. Did you find and correct the condition? | - | Go to Step 14 | Go to Step 9 |
| 7 | Test for a short to ground in the high beam headlamp relay control circuit. Did you find and correct the condition? | - | Go to Step 14 | Go to Step 9 |
| 8 | Inspect for a high resistance or a poor connection at the high beam headlamp relay in the engine fuse block. Did you find and correct the condition? | - | Go to Step 14 | Go to Step 12 |
| 9 | Inspect for a high resistance or a poor connection at the harness connector of the body control module (BCM). Did you find and correct the condition? | - | Go to Step 14 | Go to Step 13 |
| 10 | Inspect for a high resistance or a poor connection at the harness connectors of the engine fuse block. Did you find and correct the condition? | - | Go to Step 14 | Go to Step 11 |
| 11 | Replace the engine fuse block. Did you complete the repairs? | - | Go to Step 14 | - |
| 12 | Replace the high beam headlamp relay in the engine fuse block. Did you complete the repair? | - | Go to Step 14 | - |
| 13 | Replace the BCM . Refer to Control Module References for replacement and programming. Did you complete the replacement? | - | Go to Step 14 | - |
| 14 | - Use the scan tool in order to clear the DTCs.
- perate 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 B2585
DTC Descriptor
DTC B2585 : Park Lamp Control Circuit
Diagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
Park Lamp Relay Control | B2585 | B2585 | B2585 | - |
Circuit/System Description
Voltage is applied at all times to the park lamp relay from battery voltage. When the headlamp switch is placed in the PARK position, ground is applied through the headlamp switch park lamp signal circuit to the body control module (BCM). The BCM then applies a ground to the park lamp relay control circuit. This engages the relay and applies voltage through the park lamp fuses and to all the park lamps.
Conditions for Running the DTC
The ignition is ON. The park lamps must be commanded ON by the headlamp switch or by the BCM in low light conditions in AUTO mode.
Conditions for Setting the DTC
The BCM detects a short to ground, open, high resistance, or short to voltage on the park lamp relay control circuit.
Action Taken When the DTC Sets
All park lamps are inoperative.
Conditions for Clearing the DTC
- The conditions for setting the DTC are no longer present.
- A history DTC clears after 100 malfunction-free ignition cycles.
- The BCM receives the clear code command from the scan tool.
Circuit/System Verification
Ignition ON, activate the Parking Lamp output control on the scan tool. The Park Lamp Relay Command parameter in the data list should display On and the park lamps should illuminate.
Circuit/System Testing
- Ignition OFF, disconnect the engine fuse block connector J2 and test for a short to voltage, short to ground, an open, or high resistance at the connector terminal 33.
- With a scan tool, activate the Parking Lamp output control on the scan tool and test for a ground at the engine fuse block connector J2 terminal 33.
- If a ground signal is present, replace the engine fuse block. If a ground signal is not present, replace the BCM.
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
- Engine fuse block Replacement
- Control Module References for BCM replacement and programming
Trouble Code Diagnosis DTC B2625
DTC Descriptor
DTC B2625 : Display Dimming Pulse Width Modulation (PWM) Output Circuit
Diagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
LED Indicator Dimming Supply | B2625 | B2625 | B2625 | - |
Circuit/System Description
When the interior lamps dimming switch is activated, a variable voltage signal is applied through the instrument panel lamps dimmer switch signal circuit to the body control module (BCM). The BCM then applies a variable voltage signal through the LED indicator dimming supply circuit to the components on the circuit.
Conditions for Running the DTC
The ignition is ON.
Conditions for Setting the DTC
The BCM receives a ground signal on the LED indicator dimming supply circuit.
Action Taken When the DTC Sets
The BCM cease attempt to dim or illuminate the LED indicator lamps.
Conditions for Clearing the DTC
- The conditions for setting the DTC are no longer present.
- A history DTC clears after 100 malfunction-free ignition cycles.
- The BCM receives the clear code command from the scan tool.
Circuit/System Verification
Ignition ON, headlamp switch to PARK, vary the interior lamp dimming switch from dim to full bright. The LED lamps should dim and then I/P Fuse Blockome full bright.
Circuit/System Testing
- Ignition OFF, park lamps OFF, disconnect all the LED indicator dimming supply circuit lamp components on the circuit. Verify DTC B2625 does not set.
- If the DTC resets, test for a short to voltage, short to ground, or an open in the LED indicator dimming supply voltage circuit. If the circuit/connections test normal, replace the BCM, driver door switch, and passenger door switch as applicable.
- Reconnect each component one at a time andtest for the DTC B2625.
- If the DTC resets, replace that particular component.
- If the DTC does not reset, replace the BCM.
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
- Refer to the appropriate replacement procedure for the component causing the condition.
- Control Module References for BCM replacement and programming
Trouble Code Diagnosis DTC B2645
DTC Descriptor
DTC B2645 : Ambient Light Sensor Circuit Below Threshold
DTC B2645 : Ambient Light Sensor Circuit Above Threshold
Diagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
Ambient Light Sensor Signal Circuit | B2645 Ambient Light Sensor Circuit Above Threshold | B2645 Ambient Light Sensor Circuit Below Threshold | B2645 Ambient Light Sensor Circuit Above Threshold | B2645 Ambient Light Sensor Circuit Below Threshold or B2645 Ambient Light Sensor Circuit Above Threshold |
Ambient Light Sensor Ground Circuit | - | B2645 Ambient Light Sensor Circuit Below Threshold | - | B2645 Ambient Light Sensor Circuit Below Threshold or B2645 Ambient Light Sensor Circuit Above Threshold |
Circuit/System Description
The ambient light sensor is used to monitor outside lighting conditions. The ambient light sensor provides a voltage signal that will vary depending on outside lighting conditions. The body control module (BCM) provides a 10-volt reference signal to the ambient light sensor. The BCM monitors the ambient light sensor signal circuit to determine if outside lighting conditions are correct for either daytime running lights (DRL) or automatic lamp control (ALC) when the headlamp switch is in the AUTO position. In daylight conditions, the BCM will command the DRLs ON. In low light conditions, when the headlamps switch is in AUTO position, the BCM will command the low beam headlamps ON.
Conditions for Running the DTC
Battery voltage must be between 9–16 volts.
Conditions for Setting the DTC
B2645 Ambient Light Sensor Circuit Below Threshold
The DTC will set when the BCM detects voltage is low in the ambient light sensor signal circuit.
B2645 Ambient Light Sensor Circuit Above Threshold
The DTC will set when the BCM detects voltage is above 10 volts in the ambient light sensor signal circuit.
Action Taken When the DTC Sets
When DTC B2645 is present, the ALC will default to ON.
Conditions for Clearing the DTC
- The condition responsible for setting the DTC no longer exists.
- You issue a scan tool CLEAR DTCs command.
- A history DTC will clear once 100 consecutive malfunction-free ignition cycles have occurred.
Circuit/System Testing
- Ignition OFF, disconnect the ambient light sensor.
- Ignition ON, monitor the Ambient Light Sensor parameter in the BCM data list with a scan tool.
- If the scan tool parameter is less than 7 volts, locate and repair an open, high resistance, or short to ground in the ambient light sensor signal circuit, or replace the ambient light sensor.
- If the scan tool parameter is greater than10.5 volts, locate and repair a short to voltage in the ambient light sensor signal circuit.
- If circuits test OK, replace the BCM.
Repair Instructions
Perform the Diagnostic Repair VVerification completing the diagnostic procedure.
- Ambient Light Sensor Replacement
- Control Module References for BCM replacement and programming
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