Skip the auto shop - Our mechanics make house calls

Q: My theft system is keeping my car from starting in my 1994 Cadillac Deville

asked by on

I tried to start my car, and it will not start. It is telling me on my dashboard that my starting is disabled due to theft system. I've never had this issue before and I haven't done anything different with my car than my normal driving. The alarm system in my car is a system I had installed in it, years ago. I don't know why it's doing this or how to stop it so I can start my car.

My car has 201634 miles.
My car has an automatic transmission.

Hello. If the theft light is coming on then it is causing the vehicle not to start. Most of the time the issue is caused by either the key failing or the key sensor located in the key lock cylinder. There is a small chip in the key that provides resistance value to the computer to tell it that the correct key is being used. If there was a spare key I would see if that works. If it does not then it is the sensor in the key lock cylinder. Most of the time the wires from the key lock cylinder break and cause this. It can also be caused by the theft module but that is not as common. If you need to have this problem repaired, consider YourMechanic, as a certified mechanic can come to you to [diagnose why the vehicle will not start] https://www.yourmechanic.com/services/car-is-not-starting-inspection

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!
  1. Home
  2. Questions
  3. My theft system is keeping my car from starting in my 1994 Cadillac Deville

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Want to know if 88 deville 4.5 can be replaced with 4.9 easy

Hi there. With older vehicles like the 99 Cadillac, engine swaps are much easier to complete - as they are not as dependent on the ECU and modern technology to control ignition, fuel and safety systems. As such, the two...

Q: transmissions

If merely a solenoid is defective, there is no need to rebuild the transmission. What you should do is get a conclusive diagnostic (solenoids can be electrically tested) and if just "a" part is bad, replace that part. To obtain...

Q: After multiple replacement parts, car won't start - 1994 Acura Vigor

There may be an engine position sensor that has failed like a crankshaft position sensor or a cam position sensor inside the distributor. If the computer cannot tell where the engine is in its rotation or how fast its spinning,...

Related articles

P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.