Having problems with your Oldsmobile Cutlass Supreme ?
Aldl 1990 Cutlass Supreme. Drove car home. All good. Let car sit overnight. Went to start next morning. Turned key all dash lights went dim. ECM acted like it went into self test mode. Tried jumping pins A to B to read codes. When jumping pins A and B at ALDL connector all dash lights and relays go nuts. Have checked stater. Stater checks good. Checked alternator. Alternator checks good. Checked circuit wire from ECM thru ALDL to ground. Circuit good. Replaced ECM and installed original MEM-CAL
You have a defective battery.
Repair Help & Product Troubleshooting for Oldsmobile Cutlass Supreme
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