Diagnostic Instructions

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	Short to Ground	Open/High Resistance	Short to Voltage	Signal Performance
Left rear heated seat back element supply voltage	B2508 02	B1935 0C, B1935 0D	B2345 00, B2508 01	B1935 0B, B1935 0E
Left rear heated seat back element control	B2345 00, B2508 02	B1935 0C, B1935 0D	B2345 00, B2508 01	B1935 0B, B1935 0E
Left rear heated seat back temperature sensor signal	B2435 02	B1935 04, B1935 1F, B2435 0D	B1935 04, B1935 1F, B2435 0D	B1935 0A, B2345 13, B2345 42, B2345 4B
Left rear heated seat back temperature sensor low reference	--	B1935 04, B1935 1F, B2435 0D	--	B2345 13, B2345 42, B2345 4B
Left rear heated seat cushion element supply voltage	B2508 02	B2425 0C, B2425 0D	B2345 00, B2508 01	B2425 0B, B2425 0E
Left rear heated seat cushion element control	B2345 00, B2508 02	B2425 0C, B2425 0D	B2345 00, B2508 01	B2425 0B, B2425 0E
Left rear heated seat cushion temperature sensor signal	B1925 02, B2425 1F	B1925 05, B2425 04, B2425 1F	B1925 05, B2425 04, B2425 1F	B2345 13, B2345 42, B2345 4B, B2425 0A
Left rear heated seat cushion temperature sensor low reference	--	B1925 05, B2425 04, B2425 1F	--	B2345 13, B2345 42, B2345 4B
Right rear heated seat back element supply voltage	B2508 02	B2180 0C, B2180 0D	B2345 00, B2508 01	B2180 0B, B2180 0E
Right rear heated seat back element control	B2345 00, B2508 02	B2180 0C, B2180 0D	B2345 00, B2508 01	B2180 0B, B2180 0E
Right rear heated seat back temperature sensor signal	B2440 02	B2180 04, B2180 1F, B2440 05	B2180 04, B2180 1F, B2440 05	B2180 0A, B2345 13, B2345 42, B2345 4B
Right rear heated seat back temperature sensor low reference	--	B2180 04, B2180 1F, B2440 05	--	B2345 13, B2345 42, B2345 4B
Right rear heated seat cushion element supply voltage	B2508 02	B2430 0C, B2430 0D	B2345 00, B2508 01	B2430 0B, B2430 0E
Right rear heated seat cushion element control	B2345 00, B2508 02	B2430 0C, B2430 0D	B2345 00, B2508 01	B2430 0B, B2430 0E
Right rear heated seat cushion temperature sensor signal	B2170 02, B2430 1F	B2430 04, B2430 1F, B2170 05	B2430 04, B2430 1F, B2170 05	B2345 13, B2345 42, B2345 4B, B2430 0A
Right rear heated seat cushion temperature sensor low reference	--	B2430 04, B2430 1F, B2170 05	--	B2345 13, B2345 42, B2345 4B

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

Reference Information

Schematic Reference

Heated/Cooled Seat Schematics

Connector End View Reference

Heated/Cooled Seat Component Views

Electrical Information Reference

Scan Tool Reference

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.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.