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Cadillac Repair/cadillac tail lights stay on and information dash say theft system problem car may not start


hello rob i have a 97 Cadillac and the tail lights stay on even when the key is out of the front headlights cut off it started when the battery went dead charged the battery and they still are on then the information box displayed theft system problem car may not start but the car cranks and runs fine what can i do to get these problems taken care of without going to the dealership paying 500 to 700 dollars to fix it I NEED HELP


The VATS is not acting correctly and one of these days the engine will not start with that message. I would recommend bypassing the VATS, because it will leave you stranded some day. Very common!
Just contact the local alarm stores and see who can bypass it for you. Done all the time for remote start. Should cost about $60 and should get the light out.

Unfortunately, there are too many different problems that can eist on the tail lights. Could be a bad twilight sentinel, a bad ECM etc. Without being at the car, I honestly do not know.

I would never take a car to the dealer for anything but warranty and sometimes on transponder key issues and they are limited. Try to find a reputable repair garage. Most have the same diagnostic equipment a dealer does and you get by with a reasonably cost repair.

You can also attempt to purchase a Cadillac service manual from Ebay and try to diagose and repair yourself.

No matter what, the VATS has to be bypassed to prevent starting issues in the future. Think about it-1986 technology used until 2005 on the Corvettes. Relate it back to   owning a 1986 computer.

Good Luck!  

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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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