B1E99-13

B1E99-13-FRONT LEFT HEATER CONTROL CIRCUIT - CIRCUIT OPEN







- When Monitored:
With the engine running.

- Set Condition:
The Heated Seat Module (HSM) detects current below 0.5 of an amp on the (P187) Left Front Seat Heater Control circuit for more than two seconds with the output turned on.





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. Turn the Heated Seat on and operate in all modes.
6. 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 adjusting the seat.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

2. CHECK (P187) LEFT FRONT SEAT HEATER CONTROL CIRCUIT FOR AN OPEN




1. Turn the ignition off.
2. Disconnect the HSM C2 connector.
3. Disconnect the Left Seat Cushion Heater connector.
4. Disconnect the C354 in-line harness connector.

NOTE: Check connectors. Clean and repair as necessary.

5. Measure the resistance of the (P187) Left Front Seat Heater Control circuit between the HSM C2 connector and the Left Seat Cushion Heater connector (harness side).
6. Measure the resistance of the (P187) Left Front Seat Heater Control circuit between the HSM C2 connector and the C354 in-line harness connector (harness side).

Is the resistance below 5.0 Ohms for both measurements?

Yes

- Go To 3

No

- Repair the (P187) Left Front Seat Heater Control circuit for an open.
- Perform the BODY VERIFICATION TEST Body Verification Test.

3. CHECK (Z909) GROUND CIRCUIT FOR AN OPEN




1. Measure the resistance of the (Z909) Ground circuit between ground and the Left Seat Cushion Heater connector (harness side).
2. Measure the resistance of the (Z909) Ground circuit between ground and the C354 in-line harness connector (harness side).

Is the resistance below 5.0 Ohms for both measurements?

Yes

- Go To 4

No

- Repair the (Z909) Ground circuit for an open.
- Perform the BODY VERIFICATION TEST Body Verification Test.

4. CHECK FOR AN OPEN LEFT SEAT CUSHION HEATER ELEMENT




1. Measure the resistance between the (P187) Left Front Seat Heater Control circuit and the (Z909) Ground circuit at the Left Seat Cushion Heater connector (component side).

Is the resistance above 4.8 Ohms (without vented seats) or 9.8 Ohms (with vented seats)?

Yes

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

No

- Go To 5

5. CHECK PIGTAIL HARNESS AND LEFT SEAT BACK HEATER ELEMENT FOR AN OPEN




1. Measure the resistance between the (P187) Left Front Seat Heater Control circuit and the (Z909) Ground circuit at the C354 in-line harness connector (seat back side).

Is the resistance above 4.8 Ohms (without vented seats) or 11.6 Ohms (with vented seats)?

Yes

- Repair or replace the pigtail harness for an open or replace the open Seat Back Heater Element.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

No

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