Intermittent Problem Diagnosis

WARNING: This page does not describe the selected car, but rather 10 other vehicles, including the 1994 GMC Yukon, 1994 GMC Suburban, 1994 GMC Pickup, 1994 GMC Cab & Chassis, and 1994 GMC C3500 HD. However, it is still accessible from the selected car via links, so may be relevant.

Intermittent fault testing requires duplication of circuit or component failure in order to identify fault. These procedures may lead to computer recording a fault code which may help diagnosis.

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

When using a voltmeter to pinpoint faults, monitor voltage reading with ignition on or vehicle running. A change in status on voltmeter while performing test procedure indicates area of fault. See TEST PROCEDURES under INTERMITTENTS.

When using an ohmmeter to detect problems in circuit, monitor circuit resistance (ohms) with ignition switch in OFF position or with battery disconnected. A change in ohmmeter reading while performing test procedure indicates area of fault. See TEST PROCEDURES under INTERMITTENTS.