Fault Code 13 Airbag Shorted to Ground

FAULT CODE 13
Airbag Shorted to Ground

Normal Operation
The Air Bag Diagnostic Module (DM) monitors voltage level at pins 11 and 12 which varies in accordance with charging voltage. If voltage measured at these two pins falls below 2 V the MIL Lamp will illuminate and fault code 13 will be present, indicating a possible short to ground.

During the presence of fault code 13 the DM internal thermal fuse will blow, disabling the airbag deployment circuit. If voltage to pins 11 and 12 is restored after the fuse has blown, fault code 51, open internal fuse, will also be present. Fault code 13 will be present only as long as the short to ground remains.

Possible Causes
Short to ground in any of the following circuits:
- Airbag supply wiring.
- Airbag internal.
- Cable reel cassette internal.
- Safing sensor supply wiring.
- Safing sensor internal.

Fault Diagnosis
1. Airbag(s) - short circuit
- Disarm the Airbag/SRS system.
- Disconnect both airbag modules multi-plug connector.
- Switch ignition ON.
- Is fault code 13 still present?

Yes - Proceed to step 2.
No - Proceed to step 3.

2. Cable reel cassette - short circuit
- Examine wiring and connector where cable reel cassette mates to the main harness, below the steering column.
- If a fault is located, repair and proceed to step 3.
- If a fault cannot be located, disconnect cable reel cassette from main harness.
- Connect airbag simulator to the main vehicle harness in place of the cable reel cassettes.
- Measure resistance between pin 11 DM and pin 3 (ground).
- Is pin 11 short circuit to ground

No - Proceed to fault code 51.
Yes - Examine wiring and connections between DM, both airbags and safing sensor. repair faults as necessary.

3. Airbag modules - check
- Ensure shorting bar is correctly installed to passenger-side airbag connector.
- Measure resistance between connector terminals and module casing.
- If resistance value shows a short to ground, renew the module.
- If resistance shows open circuit, repeat test for driver-side module, renew as necessary.

Proceed to fault code 51 on successful diagnosis.

Electrical Schematic-Airbag Circuit Shorted To Ground, Fig.1:

1. Instrument Panel Fuse
2. Engine Compartment Fuse
3. Safing Sensor
4. Cable Reel Cassettes
MIL Lamp
5. Driver-side Airbag
6. Passenger-side Airbag
7. RH Impact Sensor
8. LH Impact Sensor
9. Air bag
10. Diagnostic Module