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2008 GMC Acadia fuse repeatedly blows

Driver front parking light not working nor are driver side rear running light or brake light, when I replace fuse for left parking light is instantly blows. Automatic w/3.6.

Then that means there is a short to ground in that circuit. Are you goi g to fix this yourself? Do you own a digital volt-ohm meter?

Agreedp it’s a dead short to ground. Ideally, the way to track this down is with a factory wiring schematic which shows all wire connectors in that particular circuit. It then becomes a matter of unplugging various connectors until the short goes away. This will at least point you into the general direction of where the short actually is.

Otherwise, it’s kind of a blind search and my preference is always a schematic so I can look things over first.

A real backyard method (and I am NOT saying to do this) is to have someone around to keep an eye out while you substitute a higher rated fuse (40 for a 20 etc) and listen for a pop or a whiff of smoke. You takes your chances with this method. I’ve done it and seen it done but it’s not a preference.

Here’s what you do . . .

remove the blown fuse

Plug in a sealed beam . . . with adapters, naturally . . . instead of the fuse

Since you’ve obviously got a direct short to ground, the sealed beam will be bright with the ignition on and light switch in the on position

Start unplugging things on that circuit, until the sealed beam turns off or becomes very dim

At that point, you’ve found the culprit

It goes without saying you need the wiring diagram for the affected circuit . . .

I’d inspect the non-working bulb’s socket area first. Good chance that’s where the problem is located. If nothing is apparent by visual inspection, might have to disconnect & remove that socket from the wiring harness to know for sure. If any of the corners have been zapped in prior fender benders, look in those areas too.