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Without Memory A45




DTC B2345 (Without Memory A45)

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

-
Front Seat Heater Disable Circuit

DTC B2345 13

-
Front Seat Heater Temperature Above Threshold

DTC B2345 42

-
Front Seat Heater Current Sensing Calibration Data Not Present

DTC B2345 4B

-
Front Seat Heater Current Sensing Calibration Data Out of Range

Diagnostic Fault Information






Circuit/System Description

The driver and passenger heated seat heating elements are controlled by a common high current relay internal to the heated seat module (HSM) and by individual low side element control circuits. The HSM connects the heater element supply voltage circuits for both seats to a common reference point. This reference point is biased to approximately 2 volts. Before the heated seat 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 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 a circuit.

Conditions for Running the DTC

The HSM must be powered.

Conditions for Setting the DTC

B2345 00

After the heated seat is activated, the HSM detects a short on either the heating element supply voltage circuit or control circuit.

B2345 13

Any temperature sensor input that remains below 1.5 volts for more that 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 passenger 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 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 (Except A45) Heated/Cooled Seat SchematicsHeated/Cooled Seat Schematics (With KA1) Heated/Cooled Seat Schematics (With KA1)Heated/Cooled Seat Schematics (With KB6) Heated/Cooled Seat Schematics (With KB6)

Connector End View Reference

Component Connector End Views A/C Compressor Clutch

Description and Operation

Heated Seats Description and Operation Heated Seats

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 Relearning for 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 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 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 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 control 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 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 3.3K 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 temperature sensor/heater element.

3. Test for greater than 3.3K 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 temperature sensor/heater element.

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 Back Cushion Heater Replacement

* Driver or Passenger Seat Cushion Heater Replacement (Passenger) Driver or Passenger Seat Cushion Heater Replacement (Passenger)Driver or Passenger Seat Cushion Heater Replacement (Driver) Driver or Passenger Seat Cushion Heater Replacement (Driver)

* Control Module References Programming and Relearning for HSM replacement, setup, and programming