For some time, I’ve been dealing with an intermittent issue with the left amber running light - See photo for clarity. The left and right light both should be on when the car is running but the left side will work sometimes and then just go dark and then come back on. It’s not a heat / cold / wet / dry related issue... it’s totally random. Grounds are good. Now, it’s staying off and the left front turn signal has stopped working. It used to work even when the running light was not working.

According to the Chilton’s wiring diagram the blue wire that send power to the amber running light goes to the Daytime Running Lamp Module. That same wire operates the turn signal. One article I read say that the DRL module controls the light on when ignition on and the BCM controls the turn signal using the same wire. Is that right?

I’ve tried to get info and wiring diagrams from All Data via a friend, but what little they found wasn’t any help.

I have confirmed continuity to the firewall. I want to check continuity back to the DRL module, but can’t find an image of what it looks like. Buick says it’s a discontinued part. Aftermarket does not seem to have one. Any resources on what one for that car looks like and availability would be greatly appreciated.

Any insight into what can be done to pinpoint the problem, would also be greatly appreciated.

 

The main reason for going to modules was to cut down on wiring required and also protect some components.

If you wanted to , either you or a saavy tech could run a wire from the light sw directly to the front marker lights completely by passing the lighting module that is not available.

It was all fine when it worked, but now if replacement parts are not available the old way they were wired may need to be utilized.