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Cadillac Repair/sunroof switch disable ignition?


My dome light panel fell off of my 1980 Seville. It looks like it has been removed before as the plastic screw brackets are broken and will not hold the unit in place. It now blocks my rear-view mirror. I unplugged the sunroof and dome light wires to remove it but now the car won't start. Does this unit have anything to do with anti theft function? Replacing the wires did not enable the ignition.


What you are referring to is the garage remote holder/dome light. The dome light and sun roof are not related to the ignition. The dome is constant power and the moon roof is switched power. Two separate circuits by themselves.

However, that is not to say that if you did this with the ignition on and you grounded the moon roof power that instead of the circuit breaker malfunctioning that you did not smoke a fusible link down by the starter.
You did not say if the engine was cranking or if the lights came on and nothing happened when you turned the key. Assuming the engine does not crank, have someone turn the ignition to start, while you have a tests light on the purple wire at the starter. If the light comes on, you have yet another problem, a bad starter. If the test light is not on, check the harness at the starter by pulling each wire. If you fried a fusible link, it will pull like rubber.
If all that is good, you will need to check the ignition switch (not the key lock cylinder) under the dash on the top of the steering column.
You also need to make sure the car does not have the after market Junk Chapman alarm. (usually have a hoodlock with a tubular key) or a stargard.
See, the factory anti thefts were so good back then that they did not disable the ignition and a thief could drive down the road with the horn honking and the lights flashing.

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Rob Painter


Alarm system questions cannot be answered on this forum. These systems are not what I can answer. Without being physically at the vehicle and not knowing what kind of electrical service has been done on the vehicle, there is no possible way to give an accurate answer over the internet. My expertise is in Ignition/key based anti-theft systems. These issues include GM VATS (resistor chip in key blade) PASSLOCK (MRD)-ignition lock rotation based, no special ignition key and the PKIII Transponder (computer chip in key) systems. These systems are not alarm based and are integral with the starting of the engine. This is why I cannot diagnose alarm problems without physically looking at the vehicle: Alarm systems are a completely different annimal than ignition key/lock based anti-theft system. Many alarm questions come from vehicles 10 years old, and since older, many hands that had been involved over the years.I am an expert in all GM factory (ignition/key based)systems. Alarm system questions pose to many situations beyond my knowledge as to what has been done to the vehicle over the years. Some guy may have actually wired the stereo into the alarm system. Who knows? Over my past 30 years in vehicle wiring repair, I have seen unbelievable wiring disaters done by guys that consider themselves "mechanics." I have seen stereos and alarms intalled using surgical tape. I have seen modules burn up, un-fused circuits, wiring jambed between the doors and even lamp cord used for a starter kill. To answer alarm questions over the internet without examining the vehicle is like asking; What does it take to remove a dent?


Education/Credentials-ASE certified. 11 years with a GM dealer and 17 years with a repair facility dealing with only the repair of theft recovered vehicles.

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