Problem Diagnosis
WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2002 GMC Savana, 2002 Chevrolet Chevy Express, 2001 GMC Savana Special, 2001 GMC Savana Camper Special, and 2001 GMC Savana. However, it is still accessible from the selected car via links, so may be relevant.
If system does not set a DTC, use scan tool or DVOM to monitor voltage or resistance values while attempting to reproduce conditions which will create an intermittent problem.
When monitoring voltage, ensure ignition switch is in RUN position or engine is running. When monitoring resistance, ensure ignition switch is in LOCK position or negative battery cable is disconnected. A status change on scan tool or DVOM while performing test procedures indicates area of problem.
Intermittent problem diagnosis requires duplication of circuit or component failure in order to identify problem. See TEST PROCEDURES . These procedures may lead to Powertrain Control Module (PCM) recording a DTC which may help diagnosis.