Chevrolet Trax: Front heated seat malfunction (with memory A45)
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.
Diagnostic Fault Information
Circuit/System Description
The driver and front passenger heated seats are controlled by separate heated
seat switches that are located in
the radio/HVAC controls. When a heated seat switch is pressed, a serial message
is sent from the radio/HVAC
controls to the HVAC control module indicating the heated seat command. The HVAC
control module then
serves as a gateway to transmit the message to the seat memory control module
via the serial data line. In
response to this message, the seat memory control module applies battery
positive voltage through the element
supply voltage circuit to the appropriate seat heating elements. The seat memory
control module then sends a
serial data message back to the HVAC control module to gateway the information
to the radio/HVAC controls
to either illuminate or turn off the appropriate temperature indicator.
Reference Information
Schematic Reference
Heated/Cooled Seat Schematics (Encore), Heated/Cooled Seat 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
Heated Seats 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 Verification
- Engine ON.
- Verify that no heated seat DTCs are set.
- If any heated seat DTC is set
Refer to Diagnostic Trouble Code (DTC) List - Vehicle
- If no heated seat DTCs are set
- Verify the scan tool Front Seat Heating Control Module Driver Seat
Heating/Venting/Cooling Mode
parameter changes between Off and Back & Cushion Heat after pressing the
driver heated seat switch.
- If the parameter does not change
Replace the K33 HVAC Control Module.
- Verify the scan tool Passenger Front Seat Heating/Venting/Cooling Mode
Switch parameter changes
between Off and Back & Cushion Heat after pressing the passenger heated seat
switch.
- If the parameter does not change
Replace the K33 HVAC Control Module.
- Refer to Circuit/System Testing.
Circuit/System Testing
- Ignition OFF, disconnect the X4 harness connector at the K40 Seat Memory
Control Module, ignition
ON.
- Verify a test lamp illuminates between the B+ circuit terminal 5 and
ground.
If the test lamp does not illuminate
- Ignition OFF.
- 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 illuminates
- Ignition OFF, connect the X4 harness connector at the K40 Seat Memory
Control Module, ignition ON,
- Verify the scan tool Seat Memory Control Module Driver Seat Heating/Venting/Cooling
Mode parameter
changes between Off and Back & Cushion Heat after pressing the driver heated
seat switch.
- If the parameter does not change
Replace the A20 Radio/HVAC Controls.
- Verify the scan tool Passenger Front Seat Heating/Venting/Cooling Mode
parameter changes between Off and Back & Cushion Heat after pressing the
passenger heated seat switch.
- If the parameter does not change
Replace the A20 Radio/HVAC Controls.
- Replace the K40 Seat Memory Control Module.
Repair Instructions
Perform the Diagnostic Repair Verification after completing the repair.
- Radio Control Assembly Replacement
- Control Module References for K40 Seat Memory Control Module replacement,
programming and
setup
READ NEXT:
FRONT SEAT HEATER CONTROL MODULE REPLACEMENT
Fig. 3: Front Seat Heater Control Module
Front Seat Heater Control Module Replacement
DRIVER OR PASSENGER SEAT BACK CUSHION HEATER REPLACEMENT
Fig.
HEATED SEATS DESCRIPTION AND OPERATION
Heated Seat Components
The driver and passenger heated seats consist of the following components:
Left heated seat switch
Right heated seat switch
HVAC contr
Schematic wiring diagrams
STEERING WHEEL SECONDARY/CONFIGURABLE CONTROL WIRING SCHEMATICS
(ENCORE)
Steering Wheel Control System
Fig. 1: Steering Wheel Control System
STEERING WHEEL SECONDARY/CONFIG
SEE MORE:
Special Tools
EN-952 Fixing Pin
EN-953-A Fixing Tool
EN-955-10 Fixing Pin from EN-955 Kit
For equivalent regional tools, refer to Special Tools.
The engine should be adjusted to TDC.
The crankshaft should be locked with EN-952 fixing pin.
The camshaft should be locked with EN-953-A fixing t
WARNING: Refer to Brake Fluid Irritant Warning .
CAUTION: Refer to Brake Fluid Effects on Paint and Electrical
Components Caution .
Inspect the brake fluid for the following conditions, indicating brake
fluid contamination:
Fluid separation, indicating 2 types of fluid are present. A substance