LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Saturn >> 1995 >> SC2 Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - System/Component Tests >> Computerized Engine Controls >> Control Unit >> Power Circuits
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Power Circuits

  1. Using a voltmeter, check for battery voltage between control unit constant battery power terminals and ground. If battery voltage is not present, check control unit power supply fuse. If fuse is okay, check for open in power supply or control unit wiring.
  2. Turn ignition switch to the ON position. Using a voltmeter, check for battery voltage between control unit ignition power terminals and ground. If battery voltage is not present, check power supply fuse(s). If fuse is okay, check for an open in wiring between fuse and control unit, or check for a defective ignition switch.
  3. Connect voltmeter between ground and control unit start (crank) signal terminal. Turn ignition switch to the START position. Battery voltage should be present between control unit start terminal and ground ONLY when ignition switch is in the START position.
  4. If voltage is not present, check fuse(s). If fuse is okay, check for an open in wiring between fuse and control unit, or check for a defective ignition switch.
scientia non olet · About LEMON Manuals