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2008 CTS interior lights wont turn off

39163 Views 40 Replies 20 Participants Last post by  redheadedrod
Hello. All of my interior lights will not turn off while I'm driving,and when I leave and Lock the car they won't turn off until the 10 min timer turns them off. The dimmer dial works and is not locked on the ON setting. When I turn the car off, and open the driver door the radio turns off, however if I open the Passenger door the radio stays on. Is there a switch located on the Passenger door that could be causing this? Thanks
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I'm not hearing the 2nd beep anymore when I lock the car so it's kind of making me feel like it could be the body control module
My first suspect is the driver's door lock actuator. If it has failed or is failing (i.e. intermittent) the BCM may not get the signal that your door is shut and it doesn't turn off the radio or interior lights. It's pretty common on these vehicles.
I actually found it. I don't know why I couldn't find it the first time I looked for it. It was turned on, some how for some reason the mechanic had to have turned it on.

Now another question, what is the battery in the trunk for? We unhooked my battery to re-set the computer and the car was completely dead, so it's not a backup battery so what's it for?
That's the main and only battery (starts and operates the car when it's not on). It's in the trunk (presumably) for weight distribution and other reasons.
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More likely a packaging problem. The cost and drop of long large cables is why a GM battery is usually near the engine/
As you suggest, there are probably packaging issues - as sportier vehicles tend to have crowded engine bays. Certainly moving the battery toward the back will mean more cabling (and weight) but it also means a slightly better front-rear weight distribution. There's also a contention that batteries fare better in the trunk or under the rear seat but I don't know if I buy that. There are trade-offs wherever the battery located.
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