Question about 1999 Cadillac DeVille

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Theft mode light

Last solution to fix problem theft lite comes on and car shuts down.been towed to cadillac dealer 4x's now.i brought your solution to him.get locksmith with v.a.t.s. to check key to wires on the bottom. he didn't get locksmith,but changed harness,couplings,ignition started drove it home, theft mode light came back on and car is sitting here for 3 days. won't start.he says he keeps replacing parts and can't figure out what is wrong with it.but says we should trade it in and get another car. what good will that do the next person that buys it?we are retired and our car is paid for. god only knows what his bill is going to be for a car we can't start.thank you for any help you can give us.

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Has anyone changed the part of the ignition switch that reads the key value and sends it to the anti-theft module, it this part malfunctions it will lock you out, and you will be unable to start the car, they are a known fault for all GM lines with factory anti-theft systems, it is part of the ignition switch, but I believe that it alone can be replaced, call your local dealer and ask about the sensor for the VATS key in the ignition, they should know what the part is formally called.

Posted on Sep 29, 2008

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Posted on Jan 02, 2017

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3 Answers

What does it mean when a 2004cadillac Deville says; starter disabled, service theft system.after key is programed?

It means you need to have it towed to the dealer , or have a mobile lock smith come to your vehicle .

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The theft light keeps blinking on and of indicating pcm 16. the car wont start until the light stops blinking though it only cranks. do you know how too reset it with the original factory key?

The PATS - passive anti-theft system light does not flash codes . Your best bet is to have your vehicle towed to a qualified repair shop or have a lock smith come fix it . You don't have the knowledge or tools to fix this problem,
The factory Passive Anti Theft System (PATS) has been activated.If the light is blinking fast, it means that the key is no longer recognized. If you have another key try that one. If not, you will have to call a locksmith or have it towed to a Ford dealer. Worst case you will need a new key. Make sure you get a spare.
The first thing to do, in just about all cases on a modern vehicle, is to scan the computers. they have lots of software that is designed to help you figure out what the problem is and there are literally thousands of trouble codes that trigger when some part of a system is failing. the people at auto zone are not trained technicians. it is like asking a clerk at a **** store to treat an illness. take your Ford or tow it to a sharp shop that knows how to do electronic/computer/anti-theft diagnosis, or you will just be wasting your time and money Good Luck!

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I have a 2010 Cadillac srx,my anti theft light came on and m vehicle wont start

What would you like to know ? What to do or how to fix ? Your best bet is have vehicle towed to the dealer.

Nov 30, 2015 | Cadillac Cars & Trucks

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Theft Protection Failure light goes on and internal electrical system shuts down

try the spare key failing which if that doesnt work then call a auto locksmith or the breakdown truck to the dealer ,the immobilisor is designed to stop auto theft and is is difficult to by-pass especially on newer vehicles

Jul 13, 2011 | Cadillac STS Cars & Trucks

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TRY TO START. DASH LITES GO OUT AND NO SOUND FROM STARTER TRYINGTO ENGAGE theft lite appears says car wont start can a bad alternator cause this problem?

No it wont. But disconnecting the battery or running it completely dead can. When the battery is disconnected the cars security goes into theft mode. I believe on yours you have to lock all the doors from the inside lock button, then shut the door. use your keys to unlock the door, put the keys in the igntion and turn it on, dont start it. wait for the light to go out. if it doesn't then start it after a minute or two..

Jun 17, 2011 | 1999 Cadillac DeVille

1 Answer

2001 Ford Taurus. Problem begins after 10 minute drive from home.Car hesitates with yelow and theft light comes on, wants to stall. Within 2 minutes, lites flash, engine dies.Will not turn over.First tow...

Yes, the chip in the key is not programmed to the computer for some reason. May have to take to dealer to fix this problem. The anti theft light coming on is a bad sign, where, for security reasons, if the key doesn't match up with what the antitheft computer expects, then the car's engine shouldn't work.

Jan 14, 2011 | 2001 Ford Taurus

1 Answer

My son has a 2003 malibu, with about 23,000 miles. Has had no problems until last friday (4 days ago) on a trip he stopped for gas, when he got back in wouldn't start, engine tries to turn but will not...

check that the theft system light is not flashing on you when trying to start it up. if it is, then it's not going to start since the car is in security mode. put the key in the ignition and turn it until the instrument panel lights light up and just leave it like that for 10 minutes until the theft system light goes off. turn the key back to off(don't take it out) and try to start it. it's a pain, espesially when you're in a hurry. to get it repaired at the dealer costs about $600-$800. I had mine done for $800.

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I have a 2002 cadillac deville, the service

i'm having the same issue. Dealer said the battery won't hold it's voltage; swapped in a new one. But also said that's independent of the "service security system" fault; which they say might be the ignition module. Were you able to fix your problem?

May 17, 2010 | 2002 Cadillac Deville

1 Answer

94 deville wont turn over, i think my alarm is in theft mode

Have the ignition fuses replaced and have the shop that installed the remote start fix the main power sorce for their unit.

Jun 14, 2009 | 1994 Cadillac DeVille

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Did the crank shaft sensor fix this permanently?


Dec 08, 2008 | 2003 Cadillac CTS

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