2003 Chevy Impala 6 cyl Front Wheel Drive Automatic 129120 miles
This post was initially to ask advice about my dashboard lights (they wouldn't come on at night).
After some troubleshooting I finally found out what was wrong: the headlight switch. One of the pin on the switch had shorted out (the one where the grey wire connects for those who may want to know).
Here is the troubleshooting procedure:
Remove the headlight switch (you have to remove, or at least losen up, the instrument panel bezel. It's easy, we're talking about 6 or 7 screws).
Once it's unplug, put a jumper across the brown/white wire and the grey wire (there are two grey wires, the one you're interested in is the one that is farthest away from the brown/white wire; NOT the one right by the brown/white wire).
When you put the jumper accross the wires, the dashboard lights should come on (make sure you do this test when it's dark around otherwise you won't see it).
If the lights do come on, replace the headlight switch ($120). If they still don't come on, you may have a module problem.