2000 deville pk3 locked out

so I have a 00 deville in the shop and I managed to lockout the PK3 system it reads service anti theft on the dash and will not start. I have tried letting it sit with key on, letting it sit with key off, the 3 10 minute cycles I just cant get this thing to start. If anyone has any ideas I would sure like to be able to drive it to the customer opposed to having it towed to the dealer!

You need to try removing the neg. terminal to yhe batt and let it sit for up to hafe an hour then replace neg. terminal and try to start. this has worked for all kinds of codes for me in the past.

tried that! I have tried everything, this car just flashes service anti theft on the display. we tried clearing the codes with a code reader and it didn't even show any codes for the antitheft system. basically this car wont start with either key or the remote start. I know the remote starter was working because I had it programmed and it started fine at least 5 times.

I would definately say, start by pulling the bypass completely out of there, and then see what happens.

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just turn key to on position and let it sit until the security light goes out.. if it keeps flashing just let it sit with the key on.. might take more than 10 minutes on some vehicles.

here is the update on the caddy: so some how I tried every option I could think of and nothing then I am sitting in the car and just doing key on,off switch keys and same thing about 3 times and the security light just went off and it started. no idea how this happened or what I did. next issue remote start module is programmed and the car starts as should but info center reads service anti theft. heres where it gets interesting, start with the key and security light stays on, and i still get service anti theft message. so I think maybe this car is seeing 2 keys so I hook up keysense to the module and now I have no more security light staying on no matter how I start it but it is still saying service anti theft. and just to take it one step further we tried to reset this code with an actual gm scan tool and it keeps coming back. the code is listed as like no key found or something like that. so everything works now I just need to figure out what the deal is with that.

I remember doing a Caddy a couple years ago. It was either a Deville or a Seville from about 2000. I kept getting the 'service anti-theft light' as well. I tried using a 457G and a GMDL-BP. The 457G had the problem almost all the time. The GMDL-BP only had the problem occassionally. I would recommend getting rid of the data bypass module and use a universal bypass module like a 556U. Hook up the keysense input as well. If the customer only has two keys and doesn't want to give one up, I recommend buying blank keys from howardkeys.com and programming a new one to the car. Blank keys cost less than the bypass module you are trying to use. Its easy...same procedure as programming a Ford key.

My other thought would be to make sure all of the Ing and ACC wires are powering on like they should. I know in some of the chevy stuff from that year there are 2 Ing and 2 ACC and i can see from DEI that this caddy dose to if you only power one of the ACC wires you will trip the anti theft light.

Where did you get power for your starter? I always grab it at the battery in those caddilacs. I've found interior power drops for a second as the BCM goes to sleep and resets the bypass module.

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Shaughn Murley
Install Manager, Dealer Services
Visions Electronics
Red Deer, Alberta