Problem Diagnosis

Intermittent problem diagnosis requires duplication of circuit or component failure in order to identify problem. See TEST PROCEDURES . These procedures may lead to computer recording a trouble code which may help diagnosis.

If problem vehicle does not produce a trouble code, use a scan tool or DVOM to monitor voltage or resistance values while attempting to reproduce conditions which will create an intermittent problem. A change in status on scan tool or DVOM indicates a problem has been located.

When monitoring voltage, ensure ignition switch is in ON position or engine is running. When monitoring resistance (ohms), ensure ignition switch is in OFF position or negative battery cable is disconnected. A status change on scan tool or DVOM while performing test procedures indicates area of problem.