Possible BCM problem?
Thread Starter
Teching In
Joined: Sep 2025
Posts: 9
Likes: 0
From: Myrtle Beach, SC
Possible BCM problem? Hi fellas, new to the forum and a new owner of a 2002 Trans Am WS6. I've only had it a couple of weeks and have had nothing but problems, which I didn't expect for a car with 67,000 miles.
The problem is the radio cuts in and out, the mirrors don't work and the passenger window can't be controlled by the driver door switch. I did a lot of reading, removed the BCM but I didnt see any solder cracks that everyone refers to. Any help will be greatly appreciated, thanks , Tom
The problem is the radio cuts in and out, the mirrors don't work and the passenger window can't be controlled by the driver door switch. I did a lot of reading, removed the BCM but I didnt see any solder cracks that everyone refers to. Any help will be greatly appreciated, thanks , Tom
Teching In
Joined: Jan 2025
Posts: 22
Likes: 3
From: USA
Check the driver's side door harness where it flexes between the door and the body. Pull back the rubber boot and look for broken wires. This is a super common problem on these cars and causes exactly the issues you're describing.
All of these problems are common for a 25 year old car... Mileage has noting to do with electrical terminals/internals corroding, plastic becoming brittle and rubber seals becoming stiff/leaking.
None of this is a BCM issue. As tmarsh518 pointed out, you could have a harness issue but I would take the door panel off and see if the plastic vapor barrier is still there. (It looks like a piece of clear plastic stuck to the door with black goo.) This keeps excess moisture away from things like the door switches. Even with the vapor barrier in place, it won't keep all the moisture/water out.
This is a common problem with the stock radios from the factory and a common issue is a dirty volume ****. If the volume **** also doesn't work correctly, then take the **** off and spray MAF cleaner down the post, turning the ****. That should clean out the dirt. If this isn't it, please post a separate thread to the Stereo and Electronics section.
Cars of this vintage will have the multi-function mirror switch fail. You can test it with an electrical diagram (download for free from Autozone.com). If you remove the switch from the trim, do so VERY carefully as the trim plastic will be brittle and it will be expensive to replace.
If one switch works and the other does not, its usually a bad switch. If you remove the switch from the trim, do so VERY carefully as the trim plastic will be brittle and it will be expensive to replace. Again, you can test this with an electrical tester before making a swap.
None of this is a BCM issue. As tmarsh518 pointed out, you could have a harness issue but I would take the door panel off and see if the plastic vapor barrier is still there. (It looks like a piece of clear plastic stuck to the door with black goo.) This keeps excess moisture away from things like the door switches. Even with the vapor barrier in place, it won't keep all the moisture/water out.
This is a common problem with the stock radios from the factory and a common issue is a dirty volume ****. If the volume **** also doesn't work correctly, then take the **** off and spray MAF cleaner down the post, turning the ****. That should clean out the dirt. If this isn't it, please post a separate thread to the Stereo and Electronics section.
Cars of this vintage will have the multi-function mirror switch fail. You can test it with an electrical diagram (download for free from Autozone.com). If you remove the switch from the trim, do so VERY carefully as the trim plastic will be brittle and it will be expensive to replace.
If one switch works and the other does not, its usually a bad switch. If you remove the switch from the trim, do so VERY carefully as the trim plastic will be brittle and it will be expensive to replace. Again, you can test this with an electrical tester before making a swap.
You need to test the switches. Less common, but check the schematic. The passenger side switch could also be bad. (Power from the driver's side flows through the passenger switch to the motor at all times.)
Thread Starter
Teching In
Joined: Sep 2025
Posts: 9
Likes: 0
From: Myrtle Beach, SC
Update: I going to say I have 3 separate problems. I tried the MAF cleaner suggested by wssix99 and that didn't work. I replaced the mirror switch, now the mirrors are working. I replaced the driver's door window switch and the passenger window does not work. The passenger door window switch does work properly. I'm assuming the radio is no good and further testing is needed between the driver door window switch and the passenger door. Thanks for the info, guys. Tom
Please create a new thread in the Stereo and Electronics section for your radio problem. We have some folks over there who can help you track down that issue.
The passenger window is a complex circuit. The drivers side switch for the passenger window has connections that flow through the passenger side switch. So, even though the passenger side switch may work the window, the switch contacts that connect the circuit for the driver's side switch can still be bad. You can also try switching the passenger side switch or test it with a simple continuity tester and schematic.
The passenger window is a complex circuit. The drivers side switch for the passenger window has connections that flow through the passenger side switch. So, even though the passenger side switch may work the window, the switch contacts that connect the circuit for the driver's side switch can still be bad. You can also try switching the passenger side switch or test it with a simple continuity tester and schematic.
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Thread Starter
Teching In
Joined: Sep 2025
Posts: 9
Likes: 0
From: Myrtle Beach, SC
Please create a new thread in the Stereo and Electronics section for your radio problem. We have some folks over there who can help you track down that issue.
The passenger window is a complex circuit. The drivers side switch for the passenger window has connections that flow through the passenger side switch. So, even though the passenger side switch may work the window, the switch contacts that connect the circuit for the driver's side switch can still be bad. You can also try switching the passenger side switch or test it with a simple continuity tester and schematic.
The passenger window is a complex circuit. The drivers side switch for the passenger window has connections that flow through the passenger side switch. So, even though the passenger side switch may work the window, the switch contacts that connect the circuit for the driver's side switch can still be bad. You can also try switching the passenger side switch or test it with a simple continuity tester and schematic.