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B1EB2-1B






B1EB2-1B-FRONT RIGHT SEAT HEATER SENSOR - CIRCUIT RESISTANCE ABOVE THRESHOLD





For a complete wiring diagram, refer to the Wiring Information.

- When Monitored:
When Heated Seat Module (HSM) is powered.

- Set Condition:
The Heated Seat Module (HSM) detects that the (P688) Right Front Heated Seat Temp Sense circuit NTC is above threshold for more than two seconds.





1. TEST FOR INTERMITTENT CONDITION

NOTE: Make sure the battery is fully charged and the charging system is operating properly before proceeding.

1. Turn the ignition on.
2. Using a scan tool, record and erase Diagnostic Trouble Codes (DTCs).
3. Turn the ignition off.
4. Start the engine and let it run.
5. Using a scan tool, read DTCs.

Is the DTC active?

Yes

- Go To 2

No

- The conditions that caused this code to set are not present at this time. Verify seat harness is routed correctly to the HSM. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors. Look for chafed, pierced, pinched, or partially broken wires and broken, bent, pushed out, spread, corroded, or contaminated terminals. Attempt to reproduce condition by operating all HSM functions one at a time. Attempt to reproduce condition by adjusting the seat.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

2. CHECK (P688) RIGHT FRONT HEATED SEAT TEMP SENSE CIRCUIT FOR A SHORT TO VOLTAGE




1. Turn the ignition off.
2. Disconnect the HSM C2 harness connector.

NOTE: Check connectors. Clean and repair as necessary.

3. Start the engine and let it run.
4. Measure the voltage of the (P688) Right Front Heated Seat Temp Sense circuit between the HSM C2 harness connector and ground.

Is there any voltage present?

Yes

- Repair the (P688) Right Front Heated Seat Temp Sense circuit for a short to voltage.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

No

- Go To 3

3. CHECK (P688) RIGHT FRONT HEATED SEAT TEMP SENSE CIRCUIT FOR A SHORT TO VOLTAGE DURING SEAT ADJUSTMENT




1. Measure the voltage of the (P688) Right Front Heated Seat Temp Sense circuit between the HSM C2 harness connector and ground while adjusting the seat in all positions.

Is there any voltage present during the seat adjustment?

Yes

- Repair the (P688) Right Front Heated Seat Temp Sense circuit for a short to voltage.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

No

- Go To 4

4. CHECK (P688) RIGHT FRONT HEATED SEAT TEMP SENSE CIRCUIT FOR A SHORT TO THE (P188) RIGHT FRONT SEAT HEATER CONTROL CIRCUIT OR TO (P187) LEFT FRONT SEAT HEATER CONTROL CIRCUIT




1. Turn the ignition off.
2. Disconnect the Right Seat Cushion Heater harness connector.
3. Disconnect the Left Seat Cushion Heater harness connector.

NOTE: Check connectors. Clean and repair as necessary.

4. Measure the resistance between the (P688) Right Front Heated Seat Temp Sense circuit and the (P188) Right Front Seat Heater Control circuit at the HSM C2 connector.
5. Measure the resistance between the (P688) Right Front Heated Seat Temp Sense circuit and the (P187) Left Front Seat Heater Control circuit at the HSM C2 connector.

Is the resistance below 10K Ohms for either measurement?

Yes

- Repair all circuits with a resistance below 10K Ohms for a short to the (P688) Right Front Heated Seat Temp Sense circuit.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

No

- Go To 5

5. CHECK (P688) RIGHT FRONT HEATED SEAT TEMP SENSE CIRCUIT VOLTAGE TO RIGHT SEAT CUSHION HEATER




1. Reconnect the HSM C2 harness connector.
2. Start the engine and let it run.
3. Measure the voltage between the (P688) Right Front Heated Seat Temp Sense circuit and the (P968) Heated Seat Sensor Return circuit at the Right Seat Cushion Heater harness connector.

Is the voltage above 4.5 volts?

Yes

- Replace the Seat Cushion Heater Element.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

No

- Go To 6

6. CHECK (P688) RIGHT FRONT HEATED SEAT TEMP SENSE CIRCUIT OR AN OPEN




1. Turn the ignition off.
2. Disconnect the HSM C2 harness connector.
3. Measure the resistance of the (P688) Right Front Heated Seat Temp Sense circuit between the HSM C2 connector and the Right Seat Cushion Heater harness connector.

Is the resistance below 5.0 Ohms?

Yes

- Go To 7

No

- Repair the (P688) Right Front Heated Seat Temp Sense circuit for an open.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

7. CHECK (P968) HEATED SEAT SENSOR RETURN CIRCUIT FOR AN OPEN




1. Measure the resistance of the (P968) Heated Seat Sensor Return circuit between the HSM C2 harness connector and the Right Seat Cushion Heater harness connector.

Is the resistance below 5.0 Ohms?

Yes

- Replace the Heated Seat Module (HSM).
- Perform the BODY VERIFICATION TEST. Body Verification Test.

No

- Repair the (P968) Heated Seat Sensor Return circuit for an open.
- Perform the BODY VERIFICATION TEST. Body Verification Test.