Driver Door Light Switch

[davidbeaver1]

On occasion I can open the driver door and the interior light won't turn on. I can shut and reopen the door and the light will then work. My understanding is that the light switch is located in the door latch. Is this something I can apply some type of lubricant to without having to remove the latch? If so, how would you go about it without damaging the switch?

 

[Fless]

You are correct that the door latch contains the switch. You didn't post your year, but also check the function of the override button on the headlight switch panel. If that gets dirty it may work the same way, incorrectly.

Here's a test -- as you're getting ready to exit leave the radio on, but remove the ignition key. As you open the door and the lights don't come on, does the radio turn off?

 

[davidbeaver1]

Sorry Fless, it is an 05 LT. I just replaced the headlight switch module because the dome override didn't work at all. I have observed that the radio does go off when you open the door, but it didn't go off once, that's what led me to the switch being stuck.

 

[smcnair]

Mine did that. Sprayed silicon spray onto the door latch and problem was solved.

 

[Fless]

Not sure if your latch is like the one in the video below (mine is), but they're not all that difficult to replace. I changed mine out last year with an OE latch from the dealer, while chasing a parasitic current draw. They do have a tendency to wear out, but simply lubing the latch mechanism might help.

This guy does a great job of showing the process of replacement:

 

[davidbeaver1]

Awesome, thanks for the video Fless and your input smcnair. I'm going to start with silicone spray and if that doesn't solve it, I'll replace it with an OEM.

 

[davidbeaver1]

Ok, so I replaced the latch today with a new one and guess what, it didn't solve the problem. It was intermittent at first like I described, then once I took the door card off, it quit working completely. The only other thing I've done is while I had the door card off, I replaced the front speaker with a new one and then went off the video above to replace the door latch. Now, the light won't come on at all! What else should I look at to troubleshoot? I did verify that the dome override switch is in the right orientation and I can open and shut any other door and the interior lights work correctly. Now when I drive the car, I have to get out, walk around to the passenger side and open and shut the passenger door to get the radio to shut off. Interesting...

 

[davidbeaver1]

To add more information, last night I disconnected the battery and left it disconnected all night (approximately 8 hours). When I connected it this morning, it did not correct the driver door light and now the passenger door is also not working. Both the rear doors turn on the interior lights, but neither front door will turn them on. Is this pointing towards the BCM? I'm not sure what else it can be...

 

[Fless]

I would do a careful check of the wires where the door hinges. Flexing over the years can compromise them there.

What if you reinstalled your old latch to see if it behaves differently? Are all of the electrical connections clean and solid?

 

[davidbeaver1]

Fless, just re-installed the old latch. While I had everything apart, I checked every connection to make sure they were solid and tight. I also checked the wires at the door hinge and they also look just fine. I still have the same results, no interior lights on either the driver door or the passenger door. However, both rear doors set off the interior lights. One test I tried was cranking the Tahoe, closing all the doors, turned on the radio, then shut the car off. The correct response would be that the radio stays on until one of the doors is opened. However now the radio just goes off when you turn the switch off. I watched this video earlier and thought about trying what he tried and wondered if it was a relay gone bad.