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B2345



DTC B2345

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Initial Inspection and Diagnostic Overview
* 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 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 front seat heating elements are controlled by a common high current relay internal to the Memory Seat Module (MSM) and on the low side by individual element control circuits. The module connects the heated seat heater element supply voltage circuits to a common reference point. This reference point is biased to approximately 2.0 volts. Before the module 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 module 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 MSM must be powered.

Conditions for Setting the DTC

B2345 00

After a heated seat is activated, the MSM 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 1.5 volts for a seat back or 0.95 volts for a seat cushion more than 1 second.

B2345 42

The current sensing calibration data is out of range.

B2345 4B

The current sensing calibration data is not programmed.

Action Taken When the DTC Sets

The heated seat functions 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.

Circuit/System Testing

B2345 00

1. Ignition OFF, disconnect the X1, X4 harness connectors at the MSM.
2. Test for infinite resistance between the driver seat heating element supply voltage circuit terminal 14 X1 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 14 X1 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 6 X1 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 6 X1 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, X5 harness connectors at the MSM.
2. Test for greater than 850 ohms between the following seat cushion temperature sensor signal circuits and the low reference circuits:

* Driver seat cushion terminal 1 X5 and terminal 3 X2
* Passenger seat cushion terminal 2 X5 and terminal 6 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 affected seat cushion heater element.

3. Test for greater than 850 ohms between the following seat back temperature sensor signal circuits and the low reference circuits:

* Driver seat back terminal 4 X5 and terminal 2 X2
* Passenger seat back terminal 3 X5 and terminal 5 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 affected seat back heater element.

4. If the circuits test normal replace the MSM.

B2345 42 or B2345 4B

If this DTC is retrieved as a current DTC, replace the MSM.

Repair Instructions

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

* Driver Seat and Passenger Seat Back Cushion Heater Replacement
* Driver Seat and Passenger Seat Cushion Heater Replacement