No immobilizer?

[El ZippiZappe]

I have a '09 purchased from rental car stock. The lock cylinder was recently replaced (by an independent shop), requiring a new key. The independent told me to have the computer re-flashed at the dealer. Dealer says that there is an error message about no theft deterrent module and they can't reflash the computer. I know of an immobilizer on some models, but my model does not have an immobilizer. (I removed the steer column covers and it's not there; nor is there an open plug/wire.)

There are no DTC's.
Start is strong, but I must use a 'modified key technique', kind of like bumping the key, which hardly ever works on the first or second time, but it seems to consistently work...


1. Do all '09 models have an immobilizer?
2. If there is a theft deterrent module, rather than an immobilizer, where might I look to find it?

I need you smart folks to save me!

[Jim2029]

I'm a tech at a local GM dealership. I looked up on GM's "SI" to see if I needed to program a new key for my 2006. It showed using the Tech2 to program it. So I had parts department order the proper key instead of using a plain key we had laying around. We cut it and I went to program it during my lunch break.

I tried with both of out Tech2's and I kept getting "Unable to communicate to Theft Deterrent Module". After about ten minutes of this, I just tried the new key and it works fine. Kicked myself in the ass for ordering the $$$ "right" key.

FWIW, mine is a 2006 Special Value Model. Stick. No options.

[El ZippiZappe]

This is a possible solution I hope is the answer. I'll give it a try. I'm assuming your car doesn't have the "immobilizer"?

thanks,

chas.

I'm a tech at a local GM dealership. I looked up on GM's "SI" to see if I needed to program a new key for my 2006. It showed using the Tech2 to program it. So I had parts department order the proper key instead of using a plain key we had laying around. We cut it and I went to program it during my lunch break.

I tried with both of out Tech2's and I kept getting "Unable to communicate to Theft Deterrent Module". After about ten minutes of this, I just tried the new key and it works fine. Kicked myself in the ass for ordering the $$$ "right" key.

FWIW, mine is a 2006 Special Value Model. Stick. No options.

[NirvAveo]

Can you elaborate on the "modified key technique"?

I've been having issues with my car starting which my dealership insisted was the immobilizer causing issues, but I can't seem to get a definitive answer about how the immobilizer system works and if the starting problem really is linked to that (cranking but no ignition). The car's been in since last week because they're doing full diagnostics and checking wiring etc...

[El ZippiZappe]

I'd like to know what your techs find.

The 'normal' technique to start the car is to turn the key to start, listen for the engine to start, and then release the key. This never works since my lock cylinder was replaced. Consequently, I tried other options. Here's what seems to work. I turn the car ON, and leave it in that mode until all the dash lights are finished - I want to make sure the computer has time to "wake up". After I do that, rather than simply turn the key to start, I bump it: give it the quickest movement to start that I can but with an immediate release. The typical pattern is that about the 3rd or 4th time, the car starts. Sometimes it is the first bump. If the car hasn't started by the 4th time, I turn everything off and start the pattern again. I have yet to find this doesn't work....

Love to know what your guys find.

[NirvAveo]

They seem to have changed their minds and say that the problem is caused by a sensor responsible for fuel regulation which is faulty. I should get the car back first or second week of Jan, and can hopefully find out the exact part that went bad.

[petrified.rabbit]

Just to answer your initial question, since i didn't see it answered. My 09 did not have the immobilizer.