B0193

DTC B0193

Diagnostic Instructions

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

* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.

* Diagnostic Procedure Instructions Diagnostic Procedure Instructions provides an overview of each diagnostic category.

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/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

* Vehicle in Service Mode.

* 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 Electrical Diagrams

Connector End View Reference

Component Connector End Views Hybrid/EV Battery Pack X1

Description and Operation

Automatic HVAC Description and Operation HVAC - Automatic

Electrical Information Reference

* Circuit Testing Circuit Testing

* Connector Repairs Connector Repairs

* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections

* Wiring Repairs Wiring Repairs

Scan Tool Reference

Control Module References Programming and Relearning for scan tool information

Circuit/System Testing

1. Vehicle OFF and all vehicle systems OFF, disconnect the X1 harness connector at the K8 blower motor control module. It may take up to 2 minutes for all vehicle systems to power down.

2. Test for less than 10 ohms between the ground circuit terminal 5 and ground.

• If 10 ohms or greater

1. Vehicle OFF.

2. Test for less than 2 ohms in the ground circuit end to end.

• If 2 ohms or greater, repair the open/high resistance in the circuit.

• If less than 2 ohms, repair the open/high resistance in the ground connection.

• If less than 10 ohms

3. Vehicle in Service Mode.

4. Verify a test lamp illuminates between the B+ circuit terminal 6 and ground.

• If the test lamp does not illuminate and the circuit fuse is good

1. Vehicle OFF.

2. Test for less than 2 ohms in the B+ circuit end to end.

• If 2 ohms or greater, repair the open/high resistance in the circuit.

• If less than 2 ohms, 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

1. Vehicle OFF.

2. Test for infinite resistance between the B+ circuit and ground.

• If less than infinite resistance, repair the short to ground on the circuit.

• If infinite resistance, replace the K8 blower motor control module.

• If the test lamp illuminates

5. Vehicle in Service Mode.

6. Test for greater than 11 V between the B+ terminal 6 and the control circuit terminal 3.

• If less than 11 V

1. Vehicle OFF, disconnect the harness connector at the K33 HVAC control module.

2. Test for less than 1 V between the control circuit and ground.

• If 1 V or greater, repair the short to voltage on the circuit.

• If less than 1 V

3. Test for less than 2 ohms in the control circuit end to end.

• If 2 ohms or greater, repair the open/high resistance in the circuit.

• If less than 2 ohms, replace the K33 HVAC control module.

• If 11 V or greater

7. Verify the voltage reading changes 0.01 V or greater with each blower speed change.

• If the voltage reading does not change

1. Vehicle OFF, disconnect the harness connector at the K33 HVAC control module, Vehicle in Service Mode.

2. Test for infinite resistance between the control circuit and ground.

• If less than infinite resistance repair the short to ground on the circuit.

• if infinite resistance, replace the K33 HVAC control module.

• If the voltage reading changes

8. Vehicle OFF, disconnect the X2 harness connector at the K8 blower control module.

9. Install a 10 A fused jumper wire between the B+ circuit terminal 1 X2 and the B+ circuit terminal 6 X1.

10. Verify the M8 blower motor turns on when installing a jumper wire between the control circuit terminal 2 X2 and ground.

• If the blower motor does not turn on
Replace the M8 blower motor

• If the blower motor turns on

11. All OK.

Repair Instructions

Perform the Diagnostic Repair Verification Verification Tests after completing the repair.

* HVAC Component Replacement Reference HVAC Component Replacement Reference

* Control Module References Programming and Relearning for HVAC control module replacement, programming and setup