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 Instructionsprovides an overview of each diagnostic category.
DTC Descriptors
DTC B2345 00
- Seat Heater Disable Circuit
DTC B2345 13
- Seat Heater Elements Temperature Above Threshold
DTC B2345 42
- Seat Heater Elements Current Sensing Calibration Not Programmed
DTC B2345 4B
- Seat Heater Elements Current Sensing Calibration Out of Range
Diagnostic Fault Information
Circuit/System Description
The front seat heating elements are controlled by a common high current relay internal to the heated seat control module (HSM) and on the low side by individual element control circuits. The HSM connects the seat heater element supply voltage circuits to a common reference point. This reference point is biased to approximately 2.5 V. 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 battery 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 circuit.
Conditions for Running the DTC
The HSM must be powered.
Conditions for Setting the DTC
B2345 00
After a heated seat is activated, the HSM detects a shorted circuit on the seat heating element supply voltage circuit or control circuit.
B2345 13
Any of the temperature sensor inputs remains below 1.45 V for more than 1 second.
B2345 42
The current sensing calibration is not programmed.
B2345 4B
The current sensing 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 clears when the malfunction is no longer present and the power mode changes to 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 [1][2]Electrical Diagrams
Connector End View Reference
Component Connector End Views Connector End Views By Name
Description and Operation
Heated Seats 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 Relearningfor 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 not the specified value, test the control circuits listed below for a short to ground:
* Driver seat cushion and seat back element terminal 3
* Driver seat cushion element terminal 5
* Driver seat back element terminal 1
3. Test for infinite resistance between the control circuit terminal 6 and ground.
• If not the specified value, test the control circuits listed below for a short to ground:
* Passenger seat cushion and seat back element terminal 6
* Passenger seat cushion element terminal 2
* Passenger seat back element terminal 4
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 circuits listed below for a short to voltage:
* Driver seat cushion and seat back element terminal 3
* Driver seat cushion element terminal 5
* Driver seat back element terminal 1
5. Verify that a test lamp does not illuminate between the supply voltage circuit terminal 6 and ground.
• If the test lamp illuminates, test the control circuits listed below for a short to voltage:
* Passenger seat cushion and seat back element terminal 6
* Passenger seat cushion element terminal 2
* Passenger seat back element terminal 4
6. If all circuits test normal, replace the HSM.
B2345 13
1. Ignition OFF, disconnect the X2, X4 harness connectors at the HSM.
2. Test for greater than 850 Ohms between the signal and the 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 value, test for a short between the signal and low reference circuits. If the circuits test normal, replace the appropriate seat cushion heater element/temperature sensor.
3. Test for greater than 850 Ohms between the signal and the low reference circuits listed below:
* Driver seat back terminal 19 X4 and terminal 5 X2
* Passenger seat back terminal 10 X4 and terminal 7 X2
• If less than the specified value, test for a short between the signal and low reference circuits. If the circuits test normal, replace the appropriate seat back heater element/temperature sensor.
4. 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
* Driver or Passenger Seat Cushion Heater Replacement
* Control Module References Programming and Relearningfor the HSM replacement, setup, and programming