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Rear Seat




DTC B2345 (Rear Seat)

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 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 RHSM must be powered.

Conditions for Setting the DTC

B2345 00

After the heated seat is activated, the RHSM 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 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.

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 (KA1) (Heated Seats Description and Operation (KA1))Heated Seats Description and Operation (KA6) (Heated Seats Description and Operation (KA6))
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)for scan tool information

Circuit/System Testing

B2345 00
1. Ignition OFF, disconnect the X1 harness connector at the RHSM.
2. Test for infinite resistance between the control circuit terminal 3 and ground.

If not the specified value, test the control circuit for a short to ground.

3. Test for infinite resistance between the control circuit terminal 6 and ground.

If not the specified value, 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 RHSM.

B2345 13
1. Ignition OFF, disconnect the X2, X4 harness connectors at the RHSM.
2. Test for greater than 850 ohms between the signal circuit and low reference circuits listed below:

* Left rear seat cushion terminal 9 X4 and terminal 6 X2
* Right rear 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 cushion heater element/temperature sensor.

3. If all circuits test normal, replace the RHSM.

B2345 42 or B2345 4B

If either DTC is set, replace the RHSM.

Repair Instructions

Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.

* Rear Seat Cushion Heater Replacement (Rear Seat Cushion Heater Replacement)
* Control Module References (Programming and Relearning)for RHSM replacement, setup, and programming