Diagnosing Customer Concerns Without Hard Diagnostic Trouble 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 (14B056) and repeat repairs. The air bag diagnostic monitor does not contain any memory of the diagnostic trouble code after the ignition switch lock cylinder (11582) is turned off. If the diagnostic trouble code is unknown, instruct the customer on how to count a code.

• Demonstrate a diagnostic trouble code by disconnecting the radiator support primary crash sensor and brackets, turn the key to RUN, and allow customer to count code.
• Reconnect the radiator support primary crash sensor and bracket and instruct customer to return when the code is known.

Once the code is known, read the Normal Operation section of the pinpoint test for the diagnostic trouble code involved.

• Study the circuit diagram and determine the location of components involved in creating that fault code.
• Do a thorough visual inspection of components, connectors, splices and wiring harnesses, looking for pinched wires, worn insulation on conductors, open, shorts, or loosely mounted sensors.

The Possible Causes section of the pinpoint test 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.