B2345
DTC B2345
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (Initial Inspection and Diagnostic Overview) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Initial Inspection and Diagnostic Overview) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Initial Inspection and Diagnostic Overview) provides an overview of each diagnostic category.
DTC Descriptors
DTC B2345 00
- Seat Heater Elements Short to Ground or Short to Battery
DTC B2345 4B
- Seat Heater Elements Current Sensing Calibration Out of Range
DTC B2345 13
- Seat Heater Elements Temperature Above Threshold
DTC B2345 42
- Seat Heater Elements Current Sensing Calibration Not Programmed
Diagnostic Fault Information
Circuit/System Description
The driver and front passenger heated seat heating elements are controlled by a common high current relay internal to the memory seat module (MSM) and the low side by individual element control circuits. The MSM connects the heated seat heater element supply voltage circuits for both seats to a common reference point. This reference point is biased to approximately 2.0 volts. Before the memory seat module will allow heated seat operation, it checks to see if this reference voltage is shorted to ground or battery voltage. Once the module verifies that it is not closing to 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 MSM must be powered.
Conditions for Setting the DTC
B2345 00
After the heated seat is activated, the MSM detects a shorted circuit on the seat heating element supply voltage circuit or control circuit.
B2345 13
Any temperature sensor input that remains below 1.5 volts for more than 1 second.
B2345 42
This DTC will set if the MSM calibration is not programmed.
B2345 4B
This DTC will set if the MSM 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 the 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 ([1][2]Electrical Diagrams)
Connector End View Reference
Component Connector End Views (Connector Views)
Description and Operation
Heated Seats Description and Operation (Description and Operation)
Electrical Information Reference
* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)
Scan Tool Reference
Control Module References (Programming and Relearning)
Circuit/System Testing
B2345 00
1. Ignition OFF, disconnect the X1 and X4 harness connectors at the MSM.
2. Ignition OFF, test for infinite resistance between the driver seat heating element supply voltage circuit terminal 6 and ground.
• If less than the specified range, test the supply voltage circuit and the seat cushion and seat back heating element control circuits for a short to ground.
3. Ignition ON, verify that a test lamp does not illuminate between the supply voltage circuit terminal 6 and ground.
• If the test lamp illuminates, test the supply voltage circuit and the seat cushion and seat back heating element control circuits for a short to voltage.
4. Test for infinite resistance between the passenger seat heating element supply voltage circuit terminal 14 and ground.
• If less than the specified range, test the supply voltage circuit and the seat cushion and seat back heating element control circuits for a short to ground.
5. Ignition ON, verify that a test lamp does not illuminate between the supply voltage circuit terminal 14 and ground.
• If the test lamp illuminates, test the supply voltage circuit and the seat cushion and seat back heating element control circuits for a short to voltage.
6. If all circuits test normal, replace the MSM.
B2345 13
1. Ignition OFF, disconnect the X2 and X4 harness connectors at the MSM.
2. Ignition OFF, test for greater than 2.2K ohms of resistance between the following seat cushion temperature sensor signal circuits and the low reference circuits:
* Driver seat cushion terminal 1 (C5) and terminal 3 (C2)
* Passenger seat cushion terminal 2 (C5) and terminal 6 (C2)
• 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 temperature sensor.
3. Test for greater than 3.2K ohms of resistance between the following seat back temperature sensor signal circuits and the low reference circuits:
* Driver seat back terminal 4 (C5) and terminal 2 (C2)
* Passenger seat back terminal 3 (C5) and terminal 6 (C2)
• 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 temperature sensor.
4. If all circuits test normal, replace the MSM.
B2345 42 or B2345 4B
If either DTC is set, replace the MSM.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
* Driver Seat Back Cushion Heater and Passenger Seat Back Cushion Heater Replacement (Driver Seat Back Cushion Heater and Passenger Seat Back Cushion Heater Replacement)
* Driver Seat Cushion Heater and Passenger Seat Cushion Heater Replacement (Driver Seat) (Driver Seat Cushion Heater and Passenger Seat Cushion Heater Replacement (Driver Seat))Driver Seat Cushion Heater and Passenger Seat Cushion Heater Replacement (Passenger Seat) (Driver Seat Cushion Heater and Passenger Seat Cushion Heater Replacement (Passenger Seat))
* Control Module References (Programming and Relearning) for MSM replacement, setup, and programming