I noticed my rear light would occasionally light up, then one day it didn't light up at all. I checked and changed the bulbs, but still had no luck getting it to light up. Testing with my multimeter, I found I wasn't getting 12V to he bulbs...checked fuses and they were fine, so I decided to pull the assembly out and take a detailed look.
Taking the assembly out of the car:
Remove the lens and bulbs (optional):
Carefully use a flat screwdriver or plastic pry bar between the headliner and the assembly to pry out the back of the lamp assembly:
Drop the back of the assembly out and the front will follow. Disconnect the connector and remove it from the vehicle:
Set it on your workbench and inspect it:
What you are looking for is the suspect cracked solder joint on the mainboard:
From here, you'll need to get out your solder iron and possibly some flux and solder to repair the joint. Here's a quick video of my iron and you'll see how just a touch will repair the joint. I added a bit of paste flux, then later I did go back and tinned my solder tip to add just a bit of additional solder to the joint. so use this video as a reference, but use your best judgement and add solder if you need to:
[youtube]http://www.youtube.com/watch?v=3wyRrCg9HU8[/youtube]
Reassemble in reverse and your light should work again.
