B2345

DTC B2345

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 Descriptor

DTC B2345 00: Seat Heater Disable Circuit.
DTC B2345 13: Seat Heater Disable Circuit Voltage Low / High Temperature.
DTC B2345 42: Seat Heater Disable Circuit Calibration Data Set Not Programmed.
DTC B2345 4B: Seat Heater Disable Circuit Calibration Not Learned.

Diagnostic Fault Information






Circuit/System Description

The left and right rear seat heating elements are controlled by a common high current relay internal to the rear heated seat module (RHSM) and the low side by individual element control circuits. The RHSM connects the 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 RHSM 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 heated seat system is active.

Conditions for Setting the DTC

B2345 00
- After the heated seat is activated, the heated seat module 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 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 rear passenger seats will be disabled.

Conditions for Clearing the DTC

- The current DTC will clear 3 seconds after the reference voltage returns to normal operating range 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.

Circuit/System Testing

B2345 00

1. Ignition OFF, disconnect the C1 harness connector at the RHSM.
2. Test for infinite resistance between the supply voltage circuit terminal 3 and ground.
-> If not the specified value, test the supply voltage circuit and the control circuits listed below for a short to ground.
- Left rear seat cushion element terminal 5.
- Left rear seat back element terminal 1.
3. Test for infinite resistance between the supply voltage circuit terminal 6 and ground.
-> If not the specified value, test the supply voltage circuit and the control circuits listed below for a short to ground.
- Right rear seat cushion element terminal 2.
- Right rear seat back element terminal 4.
4. Ignition ON, verify that a test lamp does not illuminate between the supply voltage circuit terminal 3 and ground.
-> If the test lamp illuminates, test the supply voltage circuit and the control circuits listed below for a short to voltage.
- Left rear seat cushion element terminal 5.
- Left rear seat back element terminal 1.
5. 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 control circuits listed below for a short to voltage.
- Right rear seat cushion element terminal 2.
- Right rear seat back element terminal 4.
6. If all circuits test normal, replace the RHSM.

B2345 13

1. Ignition OFF, disconnect the C2, C4 harness connectors at the RHSM.
2. Test for greater than 2.1K ohms between the signal circuit and low reference circuits listed below:
- Left rear seat cushion terminal 9 C4 and terminal 6 C2.
- Right rear seat cushion terminal 20 C4 and terminal 8 C2.
-> 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 cushion temperature sensor.
3. Test for greater than 2.0K ohms between the signal circuit and low reference circuits listed below:
- Left rear seat back terminal 19 C4 and terminal 5 C2.
- Right rear seat back terminal 10 C4 and terminal 7 C2.
-> 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 back temperature sensor.
4. If all circuits test normal, replace the RHSM.

B2345 42 or B2345 4B

If either DTC is set, replace the RHSM.