Diagnosing Customer Concerns w/out Hard Fault Codes

If a Diagnostic Trouble Code (DTC) is reported by the customer but is not present when the vehicle comes in for service, pinpoint diagnostics cannot be used. Following the pinpoint tests or fault tree diagnosis when the code is not flashing will result in needless replacement of the air bag diagnostic monitor and repeat repairs.

The air bag diagnostic monitor does not contain any memory of the DTC after the ignition switch lock cylinder is turned OFF. If the code is unknown, instruct the customer on how to count a code.

- Demonstrate a DTC by disconnecting a center or front air bag sensor, turn the ignition switch lock cylinder to the ON position, and allow customer to count DTC.
- Reconnect the sensor and instruct customer to return when the code is known.

Once the diagnostic trouble code is known, read "Normal Operation" within the pinpoint test notes for the code involved.
- Study the circuit diagram and determine the location of components involved in creating that code.
- Do a thorough visual inspection of components, connectors, splices and wiring harnesses, looking for pinched wires, worn insulation on conductors, opens, shorts, or loosely mounted sensors.

"Possible Causes" within the pinpoint test notes lists the common concerns that relate to that particular code. Each concern is listed in the order in which it is most likely to occur.