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B1E9D-11






B1E9D-11-FRONT LEFT VENT CONTROL CIRCUIT - CIRCUIT SHORT TO GROUND







- When Monitored:
With the engine running.

- Set Condition:
The Heated Seat Module (HSM) detects Voltage below 1.0 Volt or current above threshold on the (P421) Left Seat Vent Feed circuit for more than 12 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 Vented Seat on and wait at least 12 seconds before proceeding.
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 (P421) LEFT SEAT VENT FEED CIRCUIT AND VENT MOTORS FOR A SHORT TO GROUND




1. Turn the ignition off.
2. Disconnect the HSM C5 connector.

NOTE: Check connectors. Clean and repair as necessary.

3. Connect an ammeter between the (P921) Left Seat Vent Return circuit and ground at the HSM C5 connector.
4. Connect one end a fused jumper wire to Battery Voltage and the other end to the (P421) Left Seat Vent Feed circuit at the HSM C5 connector.

NOTE: Both vent motors should be operational and the ammeter should read 720 to 880 ma.

Does the ammeter read 720 ma to 1.2 amps?

Yes

- Disconnect the fused jumper wire and ammeter. Replace the Heated Seat Module (HSM).
- Perform the BODY VERIFICATION TEST. Body Verification Test.

No

- Disconnect the fused jumper wire. Go To 3

3. CHECK (P421) LEFT SEAT VENT FEED CIRCUIT AND SEAT BACK VENT MOTOR FOR A SHORT TO GROUND




1. Disconnect the Left Seat Cushion Vent connector.

NOTE: Check connectors. Clean and repair as necessary.

2. Connect an ammeter between the (P921) Left Seat Vent Return circuit and ground at the HSM C5 connector.
3. Connect one end of a fused jumper wire to Battery Voltage and the other end to the (P421) Left Seat Vent Feed circuit at the HSM C5 connector.

NOTE: The seat back vent motor should be operational and the ammeter should read 320 to 480 ma.

Does the ammeter read 320 to 600 ma?

Yes

- Disconnect the fused jumper wire and ammeter. Replace the Seat Cushion Vent Motor.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

No

- Disconnect the fused jumper wire and the ammeter. Go To 4

4. CHECK (P421) LEFT SEAT VENT FEED CIRCUIT FOR A SHORT TO GROUND




1. Disconnect the C354 in-line harness connector.

NOTE: Check connectors. Clean and repair as necessary.

2. Measure the resistance of the (P421) Left Seat Vent Feed circuit between ground at the HSM C5 connector.

Is the resistance below 10K Ohms?

Yes

- Repair the (P421) Left Seat Vent Feed circuit for a short to ground.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

No

- Go To 5

5. CHECK (P421) LEFT SEAT VENT FEED CIRCUIT FOR A SHORT TO (P921) LEFT SEAT VENT RETURN CIRCUIT




1. Measure the resistance between the (P421) Left Seat Vent Feed circuit and the (P921) Left Seat Vent Return circuit at the HSM C5 connector.

Is the resistance below 10K Ohms?

Yes

- Repair the (P421) Left Seat Vent Feed circuit for a short to the (P921) Left Seat Vent Return circuit.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

No

- Repair or replace the pigtail harness for a short to ground or replace the shorted Seat Back Vent Motor.
- Perform the BODY VERIFICATION TEST. Body Verification Test.