Chevrolet Trax: DTC B0193: Front blower motor speed circuit
Diagnostic Instructions
- Perform the Diagnostic System Check - Vehicle prior to using this
diagnostic procedure.
- Review Strategy Based Diagnosis for an overview of the diagnostic
approach.
- 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 control module
has 4 circuits: a B+ input, a signal input from the HVAC control module, a B+
output to the blower motor, and a low side pulse width modulation (PWM) output.
The HVAC control module
provides a low side (PWM) signal to the blower motor control module in order to
request the blower motor
speed. The blower motor control module grounds the blower motor using a low side
PWM signal in order to
vary the blower motor speed.
Conditions for Running the DTC
- Ignition ON.
- 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
fluctuating.
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.
Diagnostic Aids
Inspect the motor shaft for rust or other foreign material which may prohibit
proper motor operation.
If the motor operates properly please reinstall it and check for Preliminary
Information or Technical Service
Bulletins.
Reference Information
Schematic Reference
HVAC Schematics (Encore), HVAC Schematics (Trax)
Connector End View Reference
WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS -
INDEX - ENCORE WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT
CONNECTOR END VIEWS - INDEX - TRAX
Description and Operation
Manual HVAC Description and Operation
Electrical Information Reference
- Circuit Testing
- Connector Repairs
- Testing for Intermittent Conditions and Poor Connections
- Wiring Repairs
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Testing
- Ignition OFF and all vehicle systems OFF, disconnect the X1 harness
connector at the K8 Blower Motor
Control Module. It may take up to 2 min for all vehicle systems to power
down.
- Test for less than 10 ohms between the ground circuit terminal 5 and
ground.
If 10 ohms or greater
- Ignition OFF.
- 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
- Ignition ON.
- 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
- Ignition OFF, remove the test lamp.
- 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
- Ignition OFF, remove the test lamp.
- Test for infinite resistance between the B+ circuit terminal 6 and
ground.
- If less than infinite resistance, repair the short to ground on the
circuit.
- If infinite resistance
- Disconnect the X2 harness connector at the K8 Blower Motor Control
Module and disconnect the harness connector at the M8
Blower Motor.
- Test for infinite resistance between the M8 Blower Motor control circuit
terminal B and ground.
- If less than infinite resistance, repair the short to ground on the
circuit.
- If infinite resistance, test or replace the M8 Blower Motor.
If the test lamp illuminates
- Ignition OFF, remove the test lamp.
- Test for 2.6-3.2 V between the control circuit terminal 3 and ground.
If less than 2.6 V
- Ignition OFF, disconnect the X2 harness connector at the K33 HVAC
Control Module, ignition
ON.
- 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.
- 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 greater than 3.2 V
- Ignition OFF, disconnect the X2 harness connector at the K33 HVAC
Control Module, ignition
ON.
- 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, replace the K33 HVAC Control Module.
If between 2.6-3.2 V
- Ignition OFF, connect the X1 harness connector at the K8 Blower Motor
Control Module and disconnect
the harness connector at the M8 Blower Motor, ignition ON and blower ON.
- Verify a test lamp illuminates between the control circuit terminal 2
and ground.
If the test lamp does not illuminate
- Ignition OFF, remove the test lamp and disconnect the X2 harness
connector at the K8 Blower
Motor Control Module.
- 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 K8 Blower Motor Control Module.
If the test lamp illuminates
- Connect a test lamp between the control circuit terminal 1 and the
control circuit terminal 2.
- Verify the test lamp becomes progressively brighter as the blower speed
is increased and progressively
dimmer as the blower speed is decreased.
If the test lamp does not illuminate
- Ignition OFF, remove the test lamp and disconnect the X2 harness
connector at the K8 Blower
Motor Control Module, ignition ON.
- Test for less than 1 V between the control circuit terminal 2 and ground.
- If 1 V or greater, repair the short to voltage on the circuit.
- If less than 1 V
- Ignition OFF.
- 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 K8 Blower Motor Control Module.
If the test lamp illuminates, but does not change in brightness
- Ignition OFF, remove the test lamp and disconnect the X2 harness
connector at the K8 Blower
Motor Control Module.
- Test for infinite resistance between the control circuit terminal 2 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 changes in brightness as the blower speed is changed
- Test or replace the M8 Blower Motor.
Repair Instructions
Perform the Diagnostic Repair Verification after completing the repair.
- HVAC Component Replacement Reference (C67), HVAC Component Replacement
Reference
(C60), HVAC Component Replacement Reference (C41)
- Control Module References for HVAC control module replacement,
programming and setup
READ NEXT:
Diagnostic Instructions
Perform the Diagnostic System Check - Vehicle prior to using this
diagnostic procedure.
Review Strategy Based Diagnosis for an overview of the diagnostic
approach.
Diag
Diagnostic Instructions
Perform the Diagnostic System Check - Vehicle prior to using this
diagnostic procedure.
Review Strategy Based Diagnosis for an overview of the diagnostic
approach.
Diag
Diagnostic Instructions
Perform the Diagnostic System Check - Vehicle prior to using this
diagnostic procedure.
Review Strategy Based Diagnosis for an overview of the diagnostic
approach.
Diag
SEE MORE:
Special Tools
CH-49375 Spanner
For equivalent regional tools, refer to Special Tools .
Removal Procedure
Remove the air inlet grille panel. Refer to Air Inlet Grille Panel
Replacement (Trax) , Air Inlet Grille
Panel Replacement (Encore) .
Fig. 32: Front Suspension Strut Mount Plate Nut Cap
NOTE: The following steps must be completed before using the
symptom tables.
Perform the Diagnostic System Check - Vehicle before using the Symptom
Tables in order to verify that
all of the following are true:
There are no DTCs set.
The control modules can communicate via the serial data l