B2345
DTC B2345
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 B2345 00
- Seat Heater Disable Circuit
DTC B2345 4B
- Seat Heater Disable Circuit Calibration Not Learned
DTC B2345 13
- Seat Heater Disable Circuit Voltage Low/High Temperature
DTC B2345 42
- Seat Heater Disable Circuit Calibration Data Set Not Programmed
Diagnostic Fault Information
Circuit/System Description
The heated seat heating elements are controlled by a common high current relay internal to the heated seat module (HSM) and by individual low side element control circuits. The HSM connects the heater element supply voltage circuits for both seats to a common reference point. This reference point is biased to approximately 2 volts. Before the HSM will allow heated seat operation, it checks to see if the heating element supply voltage circuits and control circuits are shorted to ground or voltage. Once the HSM verifies that it is not closing into a shorted heating element, it allows heated seat operation. After which it continues to monitor for a shorted a circuit.
Conditions for Running the DTC
The HSM must be powered.
Conditions for Setting the DTC
B2345 00
After the heated seat is activated, the HSM detects a short on either the heating element supply voltage circuit or control circuit.
B2345 13
Any temperature sensor input that remains below 1.5 volts for more that 1 second.
B2345 42
This DTC will set if the module calibration is not programmed.
B2345 4B
This DTC will set if the module calibration is out of range.
Action Taken When the DTC Sets
The heated seat function for both seats will be disabled.
Conditions for Clearing the DTC
* The current DTC will clear and set the code to history 3 seconds after the reference voltage returns to normal operating range and the ignition is cycled OFF then back to ACC or RUN.
* The history DTC will clear after 50 consecutive fault-free ignition cycles have occurred.
Reference Information
Schematic Reference
Heated/Cooled Seat Schematics (Electrical Diagrams)
Connector End View Reference
Component Connector End Views (Connector End Views By Name)
Description and Operation
Heated Seats Description and Operation (Description and Operation)
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
B2345 00
1. Ignition OFF, disconnect the X1 harness connector at the HSM.
2. Test for infinite resistance between the control circuit terminal 3 and ground.
• If less than the specified range, test the control circuit for a short to ground.
3. Test for infinite resistance between the control circuit terminal 6 and ground.
• If less than the specified range, test the control circuit for a short to ground.
4. Ignition ON, verify that a test lamp does not illuminate between the control circuit terminal 3 and ground.
• If the test lamp illuminates, test the control circuit for a short to voltage.
5. Ignition ON, verify that a test lamp does not illuminate between the control circuit terminal 6 and ground.
• If the test lamp illuminates, test the control circuit for a short to voltage.
6. If all circuits test normal, replace the HSM.
B2345 13
1. Ignition OFF, disconnect the X2, X4 harness connector at the HSM.
2. Test for greater than 1.9K ohms between the signal and low reference circuits listed below:
* Driver seat cushion terminal 9 X4 and terminal 6 X2
* Passenger seat cushion terminal 20 X4 and terminal 8 X2
• If less than the specified range, test for a short between the signal and low reference circuits. If the circuits test normal, replace the appropriate seat temperature sensor.
3. If all circuits test normal, replace the HSM.
B2345 42 or B2345 4B
If either DTC is set, replace the HSM.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
* Driver or Passenger Seat Back Cushion Heater Replacement (Impala) (Driver or Passenger Seat Back Cushion Heater Replacement)
* Driver or Passenger Seat Cushion Heater Replacement (Driver Only) (Driver or Passenger Seat Cushion Heater Replacement (Driver Only))
* Control Module References (Programming and Relearning) for the HSM replacement, setup, and programming