GMC Troubleshooting Questions? Ask a Mechanic for Answers
Welcome, I'm Chris (aka Moose) I prefer working afternoon till just after midnight.
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Connector 5 pin 1 yellow/blue wire at the BCM is the output voltage for the left rear turn lamp. We need to check the voltage there to see if this is a wire or BCM failure. With the truck on does the instrument cluster show door ajar with a door open and can the overhead courtesy lights be turned on manually?
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Hello again Chris here,
Here is an image of connector X5 on the BCM.
Remove the front left or right overhead lamp and switch assembly. With a door open are any of the wires powered? Wit hthe lights manually commanded on are there any wires powered? Is the blcak wire a good ground?