2009 Buick Lacrosse Interior Light Fuse Blows

This 2009 Buick Lacrosse came in with the complaint that the interior light fuse blows. The fuse is located in the passenger side interior fuse box. there is a cover on the end of the dash that covers the fuse box.

I confirmed that the interior light fuse was blown. The fuse should be labeled INT/ILLUM on the legend that is on the inside of the cover panel.

I installed a fused jumper wire that uses the cheaper ATO/ATC fuses. The fuse again blew.

After looking at wiring diagrams I realized that this fuse goes straight to the BCM and the BCM send power out on multiple leads.  I figured that the BCM area was going to be the best place to start testing. The BCM is located under the driver’s side of the dash. The under dash hush panel and the knee bolsters have to be removed to access it.

There were a couple of push pins that held on the under dash hush panel.

A side view of the push pin.

There are two screws on either side of the outer knee bolster panel that need to be removed. The screws have 7 mm heads.

There are spring clips that have to be dislodged by pulling the upper portion of the panel towards the driver’s seat.

There are a total of four 10mm headed screws that hold the inner brackets to the dash.  The forward one is accessed a shown below.

The rearward screws are accessed through the round holes on either side of the panel.

There are about half a dozen 7mm headed screws that attach the outer panel to the dash.  After removing the panel I installed a new fuse to confirm that nothing had changed.

The fsue did not blow this time and the interior lights were working properly. A closer visual inspection under the dash found these two shorted wires for the driver’s footwell light. Notice the raised aluminum mounting boss with a threaded hole. That is where the forward bolt attaches the panel to the dash carrier.

I separated the two wires.

Then cut out the bad spots and spliced the wires back together. I checked first to make sure the light would still mount in it’s holder with the wires slightly shorter. Probably could have cut out a couple of inches if I had needed to.

After I had sealed the connection with heatshrink tubing, I installed a piece of split loom to protect the harness.

I also made sure that the harness was out of the way of the bracket when I re installed the metal knee bolster.

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