Theft mode

[wesfurgason]

I have a ‘00 k2500 ccsb that is stuck in theft mode. I’ve tried bypassing the security system and replacing the bcm but I can’t get the thing to come out of theft mode or start. Any suggestions?

 

[618 Syndicate]

Gonna need more info.
Theft mode? You mean the security light is flashing?
How did you bypass security?
Also, 400's don't have a BCM (except 99/00 Esky and Denali) so I don't know what you replaced, but it wasn't that...

 

[someotherguy]

Gonna need more info.
Theft mode? You mean the security light is flashing?
How did you bypass security?
Also, 400's don't have a BCM (except 99/00 Esky and Denali) so I don't know what you replaced, but it wasn't that...

If you've got a 98-up 400 it's got what GM will sometimes refer to as a BCM. Got the TDM ("theft deterrent module") as part of it, or they're interchanging the names, either way it's the black box with green socket about the size of a deck of cards/cigarette pack, under your dash right next to the DRL diode. It's part of the Passlock system.

OP - time to have a tuner get rid of Passlock from your PCM. Once it starts giving you trouble it doesn't stop until you get rid of it.. in my opinion, anyway.

Richard

 

[HotWheelsBurban]

If you've got a 98-up 400 it's got what GM will sometimes refer to as a BCM. Got the TDM ("theft deterrent module") as part of it, or they're interchanging the names, either way it's the black box with green socket about the size of a deck of cards/cigarette pack, under your dash right next to the DRL diode. It's part of the Passlock system.

OP - time to have a tuner get rid of Passlock from your PCM. Once it starts giving you trouble it doesn't stop until you get rid of it.. in my opinion, anyway.

Richard

Yup, my experience too. My brother and Mom were thisclose to divorcing the Burb and me because of that F ing passlock. Our other 99 Burb never had the issue, but that was 9 years ago when it got wrecked. So that much time to not bounce around....
If I had been on this forum when that truck was wrecked, there's SO much stuff I would have known to pull off the carcass.....oh well. Spilt milk and all that.....

 

[wesfurgason]

Gonna need more info.
Theft mode? You mean the security light is flashing?
How did you bypass security?
Also, 400's don't have a BCM (except 99/00 Esky and Denali) so I don't know what you replaced, but it wasn't that...

I replaced the VATS. That’s what I tried bypassing as well. Yes it just won’t start because of that

 

[SUBURBAN5]

X2 get it tuned out

 

[Dariusz Salomon]

If you've got a 98-up 400 it's got what GM will sometimes refer to as a BCM. Got the TDM ("theft deterrent module") as part of it, or they're interchanging the names, either way it's the black box with green socket about the size of a deck of cards/cigarette pack, under your dash right next to the DRL diode. It's part of the Passlock system.

OP - time to have a tuner get rid of Passlock from your PCM. Once it starts giving you trouble it doesn't stop until you get rid of it.. in my opinion, anyway.

Richard

Do you think 99 Tahie would have it? What are the symptoms of this thing failing? And forgive my ignorance but what's the DRL diode? Or some more details on the location of this thing please?

 

[618 Syndicate]

I replaced the VATS. That’s what I tried bypassing as well. Yes it just won’t start because of that

You did the relearn, correct?

 

[618 Syndicate]

Do you think 99 Tahie would have it? What are the symptoms of this thing failing? And forgive my ignorance but what's the DRL diode? Or some more details on the location of this thing please?

DRL is daytime running lights. I removed the little metal box under the dash to defeat them.

 

[Dariusz Salomon]

I think I found some answers on the net-as I understand the symptom of passlock's fault is "crank no start". I had it once-and I had no idea the truck was equiped with some anti theft device. I guess when I'm done with covid I have to check if my truck has it.