Diesel Data: Automotive Repair

Troubleshooting Intermittent Failures

Troubleshooting Intermittent Failures

If there was a malfunction, that sets a DTC, but it does not recur, it will be stored in the memory as an intermittent failure, and the SRS indicator may come on depending on the malfunction detected.

NOTE: Check the condition of the battery and the charging system. Low battery voltage may cause some intermittent failures.

After checking the DTC, troubleshoot as follows:

1. Read the DTC (see "Reading the DTC").
2. Clear the DTC memory (see "How to clear the DTC Memory").
3. Set the parking brake, then start the engine, and let it idle.
4. The SRS indicator comes on for about 6 seconds and then goes off.
5. Shake the related wire harnesses and the connectors, and look for loose connections and poor grounds.
6. Take a test-drive (quick acceleration, quick braking, and cornering), turn the steering wheel fully left and right, and hold it there for 5 to 10 seconds. If the problem recurs, the SRS indicator will come on.

NOTE: A faulty cable reel can cause intermittent connections related to the driver's airbag inflator DTCs.

7. If you cannot duplicate the concern, ask the customer about the conditions when it occurred, or ask the customer to demonstrate the concern.
8. If you cannot duplicate the intermittent failure, the system is OK at this time.