Interior light issue

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Darkimag22

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My interior lights will not turn on/off with either of the doors being opened/closed (I can turn it on manually on the dash). Just this morning I found that if I hold the unlock switch down the interior lights turn on and then turn off when I release it. Any ideas what's going on??? Another thing to note, I can lock/unlock from my drivers side but when I use the passenger side all I get is a clicking sound coming from underneath the dash under the steering wheel....a bad relay maybe???

Thanks guys.
 

scottydl

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Sounds like a wire shorting out somewhere. Might need to start by checking the wire bundle running between the body and the door… on some GMs that was subject to twisting and wires breaking over time. There’s probably a black rubber accordion-like cover to peel back in the door crack so you can take a look at the wires.
 

Darkimag22

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So I replaced the relay under the steering column but still have the same issue...interior lights do not turn on when a door is opened. While under the dash, it looks like the truck had a command start installed at one time as there is a bunch of wires that have been cut/soldered or tapped into. Guess I will do my best to trace all the extra wiring, remove it and see if that helps at all.
 

98K3500Dually

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Hey, I know this is an old thread, but did you resolve this issue? I am having almost the same issue with a customers 98 K3500. Interior light comes on only when the lock/unlock button is held. Someone previously has overlayed the tan circuit from the passenger side to drivers side door. When I remove the overlay, the drivers door lock does not function.
 

Tdean91491

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Not sure if this will help you at all but hopefully it will.
 

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dave s

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My interior lights didn't work when I opened either door but did work if you used the switch. Replacing both door switches fixed it . I did not have any of your other issues though.
 

98K3500Dually

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I found a burnt trace in the RKE/RFA module and it is for the drivers door unlock command. I am going to the junkyard in hopes to find one on Friday and see if it resolves the issue. This pin is shorted to ground after repairing the trace, which leads me to believe there is a blown diode within the module.
 

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AK49BWL

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It's supposed to be shorted to ground, that's the return path for the lock command. In fact, both lines are shorted to ground when neither are activated.
 

98K3500Dually

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It's supposed to be shorted to ground, that's the return path for the lock command. In fact, both lines are shorted to ground when neither are activated.
The way the GM schematic appears, is that circuit should be “open” unless it is providing power to the unlock circuit at the drivers door. When the module is plugged in and I press the unlock button, it drew 22amps on my meter before the fuse blew. When the module is unplugged, it only draws 3amps.

Maybe I don’t understand the schematic fully, and I plan to test the new module when I get one to see if it is different. This is not a system I’ve dealt with before and is far different from the 90s Ford RKE systems I’m familiar with.
 

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