Power Circuits
WARNING: This page does not describe the selected car, but rather 35 other vehicles, including the 1992 Pontiac Trans Sport, 1992 Oldsmobile Silhouette, 1992 Oldsmobile Bravada, 1992 GMC Yukon, and 1992 GMC Vandura Special. However, it is still accessible from the selected car via links, so may be relevant.
- Using a voltmeter, check for battery voltage between ECM continuous power terminal(s) and ground. If battery voltage is not present, check for blown fuse or open fusible link. If okay, check for open in wire between ECM terminal and power source.
- Turn ignition switch on. Using a voltmeter, check for battery voltage between ECM ignition power terminals and ground. If battery voltage is not present, check IGN fuse. If fuse is okay, check for an open in wire between battery and ignition switch, and between ignition switch and ECM terminal. If okay, check for a defective ignition switch.
- Connect voltmeter between ground and ECM starter (crank) signal terminal. On vehicles with manual transmission/transaxle, depress clutch pedal. Turn ignition switch to START position. Battery voltage should be present ONLY when ignition switch is in the START position.
- If voltage is not present, check CRANK fuse or fusible link between ignition switch and ECM terminal. If fuse or fusible link is okay, check for an open in wire between ignition switch and ECM terminal, or check for a defective ignition switch.