2003 Cadillac CTS Q&A
2003 Cadillac CTS Question: Alt or ECU
If you have a multimeter you'll be able to check the alternators output at the time of the problem. Eventhough many vehicles will illuminate multiple lights when the alternator fails remember to also check your PCM operation by monitoring the data values while the engine is running. Be sure to compare the data values with the calibrated values for your vehicle. Good luck. - A1 Customs Inc.