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Discussion Starter #1
I just bought a wrecked 2004 GTO (automatic trans, hit in front and still movable but totaled) and am having a weird problem with it.

The car was delivered yesterday and the seller started it up on the trailer, put in gear and drove it off, no problem. The battery was dead so he used a jumper box.

After he left I pulled the battery, charged it for a few hours and put it back in the car. It's got plenty of charge now. You can start the car easily no problem and it runs fine, but:

1) The ignition key will not rotate all the way back to be pulled out unless the battery is disconnected. Once the battery is disconnected, the key rotates back to the pull out position and comes out

And

2) The shifter can't be moved out of park at all, battery connected or not. With the battery connected and my foot on and off the brake I can hear the shifter lockout solenoid clicking, and can see it moving (I partially removed the console to see that).

Is there some security feature triggered by maybe the BCM that is doing this? The car will ultimately be pulled apart as a donor for a swap anyway, so it's not a long term issue, but it would be nice to know now so I can still move the car around.....

Anyone see this before?

Thanks
 

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Doesn't sound like a security issue sounds like it was a wrecked issue and the transmission is screwed up.

Can't say that this issue was raised in the past as most don't buy totaled cars and ask why its messed up.

Sounds to me the lockout linkage is screwed up along with the signal to the PCM. When pulling the battery cable it resets the computer and you are able to remove the key. Then upon starting the car it locks in and stays locked until the signal is broken again. The jolt to the car may also have damaged the OBC.
 

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Discussion Starter #3
Not sure about that....

The car was driven (under it's own power) off a trailer-I watched it. There is nothing wrong with the drivetrain. This is some sort of electrical lockout/security thing. The engine runs fine- no issues. I believe the BCM has some default security feature on battery disconnect and that's where we are........
 

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The car was driven (under it's own power) off a trailer-I watched it. There is nothing wrong with the drivetrain. This is some sort of electrical lockout/security thing. The engine runs fine- no issues. I believe the BCM has some default security feature on battery disconnect and that's where we are........
The lockout linkage when working prevents someone from starting the car in gear or removing the key when the car is in gear. Your situation suggests that MAY be the issue. When the battery cable is removed, often times it resets the computer. This MAY or maybe not be your issue.

You'd still be able to drive it and the engine will work as normal, its the lockout function it seems to be the issue and with the OBC controlling things until reset then once operational the OBC is locking you. This is just a suggestion.

Your situation is not normal security of this car. A scanner could diagnose the code being thrown whether it be a BCM or the PCM.
 

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Your BTSI is screwed up. Also your Park Signal seems messed up as well.

Modern ignition systems have two functions when paired with an automatic Transmission.

The Brake Transmission Shift Interlock (BTSI) makes it such that unless your TCM sees the Brake Signal from the ABS it won't shift out of park.

The Park Signal makes is so that unless you are in park you can't take the key out. The failsafe on this is that if the car is on it sets the Park Signal high preventing you from removing the key. However if you disconnect the battery the line drops low, and you can take it out.

I'd be checking your electrical connections on the TCM, it seems like your TCM isn't on the communication bus (called GMLAN). Or there is a problem with it. Typically if your TCM is totally off the bus the PCM is as well (since GM uses a daisy chain connection system). The other option is that there is an issue between the BCM and the ignition coil (as it's directly wired to the BCM).

The PCM, TCM, ABS, and PIM are on the GMLAN in the GTO. PIM translates GMLAN to UART and the BCM, Cluster, Radio, SCM (Airbag) are all on UART.
 

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Discussion Starter #9
Not sure on that.....

I doubt the PCM has anything to do with this- there are no security feeds from it back to the car. The PCM does look for the VATS signal from the BCM, and then allows a start or not. I'm pretty sure this issue is in the BCM or interlock scenario. Checking with wiring diagrams would confirm that, so that's the next step
 

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I've always considered myself to be 'old school', however, that being said, what scares me is that I fully understood LS2 MN6's post.............
 
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