DTC B0193
Diagnostic Instructions
DTC Descriptors
DTC B0193 01: Front Blower Motor Speed Circuit Short to Battery
DTC B0193 06: Front Blower Motor Speed Circuit Low Voltage/Open
Diagnostic Fault Information
Circuit
| Short to Ground
| Open/High Resistance
| Short to Voltage
| Signal Performance
|
Blower Motor Control Module B+
| B0193 06
| B0193 06
| --
| --
|
Blower Motor Control Module Control
| B0193 06
| B0193 06
| B0193 01
| -
|
Blower Motor Control Module Ground
| -
| B0193 06
| --
| --
|
Circuit/System Description
The blower motor control module is an interface between the HVAC control module and the blower motor. The blower motor speed control from the HVAC control module, battery positive and ground circuits enable the blower motor control module to operate. The HVAC control module provides a pulse width modulation (PWM) signal to the blower motor control module in order to command the blower motor speed. The blower motor control module transfers the PWM signal into a corresponding blower motor voltage. The voltage resides between 2-13 V and changes linear to the height of the PWM signal.
Conditions for Running the DTC
• | The HVAC control module is ON. |
Conditions for Setting the DTC
B0193 01
The voltage at the HVAC control module output to the blower motor control module is always high.
B0193 06
The voltage at the HVAC control module output to the blower motor control module is always low or floating.
Action Taken When the DTC Sets
The blower motor is inoperative.
Conditions for Clearing the DTC
The condition for setting the DTC is no longer present.
Reference Information
Schematic Reference
HVAC Schematics : Automatic
Connector End View Reference
Component Connector End Views
Description and Operation
Automatic HVAC Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Testing
- Ignition OFF, disconnect the X1 harness connector at the K8 Fan Motor Control Module, ignition ON.
- Verify that a test lamp illuminates between the B+ circuit terminal 6 X1 at the K8 Fan Motor Control Module harness connector and earth.
⇒ | If the test lamp does not illuminate and the circuit fuse is good |
2.2. | Test for less than 2 Ω in the B+ circuit end to end. |
⇒ | If 2 Ω or greater, repair the open/high resistance in the circuit. |
⇒ | If less than 2 Ω, verify the fuse is not open and there is voltage at the fuse. |
⇒ | If the test lamp does not illuminate and the circuit fuse is open |
2.2. | Test for infinite resistance between the B+ circuit and ground. |
⇒ | If less than infinite resistance, repair the short to ground on the circuit. |
2.3. | Disconnect the harness connector at the M8 Blower Motor and the X2 harness connector at the K8 Blower Motor Control Module. |
2.4. | Test for infinite resistance between the B+ circuit terminal 1 X2 and earth. |
⇒ | If less than infinite resistance, repair the short to ground on the circuit. |
2.5. | Connect the harness connector at the M8 Fan Motor. |
2.6. | Install a 40 A fused jumper wire between the B+ circuit terminal 1 X2 and B+ and verify the fuse is good. |
⇒ | If the fuse is open, replace the M8 Fan Motor. |
⇒ | If the fuse is good, replace the K8 Fan Motor Control Module. |
⇓ | If the test lamp illuminates |
- Verify that a test lamp illuminates between the B+ circuit terminal 6 X1 and ground circuit terminal 5 X1.
⇒ | If the test lamp does not illuminate |
| Repair the open/high resistance in the circuit. |
⇓ | If the test lamp illuminates |
- Ignition OFF, disconnect the X2 harness connector at the K33 HVAC Control Module, ignition ON.
- Test for less than 0.3 V between the control circuit terminal 3 X1 at the K8 Blower Motor Control Module harness connector and ground.
| Repair the short to voltage on the circuit. |
- Ignition OFF.
- Test for infinite resistance between the control circuit terminal 3 X1 at the K8 Fan Motor Control Module harness connector and earth.
⇒ | If less than infinite resistance |
| Repair the short to ground on the circuit. |
- Test for less than 5 Ω between the K33 HVAC Control Module control circuit terminal 15 X2 and control circuit terminal 3 X1 at the K8 Blower Motor Control Module harness connector.
| Repair the open/high resistance in the circuit. |
- Replace the K8 Fan Motor Control Module and verify the DTC does not reset.
| Replace the K33 HVAC Control Module. |
- All OK.
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
© Copyright Chevrolet. All rights reserved |
© Copyright Chevrolet. All rights reserved |