Hello,
My fog lights are not working, found out while getting inspected. They wanted $175 to replace, I did it myself in 10 minutes for $10. However, new bulbs did not solve the problem.
Here's what else I did:
-checked that the high beams were not on.
-checked that the illumination light on the switch was working properly.
-swapped fuses (1 and 6) and relays (37, 39) to no effect.
-cleaned out ground connectors on the front right and left side of the engine.
-Checked DTC codes and found a few, B0605H (BCM internal memory function), U1255, U1096, U1064, U1026 (loss of communication with PCM, DCM, IPC).
-Searched the forum to get most of the ideas listed above.
-Searched my facory manual looking for something else to try and/or the source of that unplugged wire connector.

Any ideas would be much appreciated!!
Greg

I also found a 2 plug connector near the right fog light that was not plugged into anything (both wires were Green with black lines).

 

OK, it's getting worse. Now my left front headlight went out (coincidence?) and my orange blinker lights don't turn on when I unlock the car with my key fob!

I'm going to replace both headlamps.

I've been staring at schematics from the factory manual and reading prior posts explaining how the circuit works (thx Toddff from 3-29-2009). I've now found the correct fuses (32 in istrument panel and 6 in engine compartment) and verified to be ok. The relay is ok as previously checked. I've also verified that I've cleaned the ground for this circuit (splice pack 100, ground 102).

I'm not quite ready to concede my BCM is fried but might be heading in that direction. This is my first time looking at schematics (very confusing!). I first want to find out why I have an unplugged wire sitting near the front headlight assembly (2-wire connector, both wires are green/black). Being cynical, I'm still worried the shop may have disconnected on purpose.

Greg



Quote:
With the ignition switch in the ON position, and the park lamps or low beam headlights on, the fog lights will illuminate when the driver presses the fog lamp switch. The F/TNKDR fuse 32 in the instrument panel fuse block supplies battery positive voltage to the fog lamp switch contacts. Battery positive voltage may also by applied to the FOG LP relay 39. When the fog lamp switch is pressed, battery positive voltage is applied to the BCM. The BCM applies a ground to the FOG LP relay 39 coil circuit, which energizes the fog lamp relay coil control circuit. The current flow is now from the fog lamp relay to both front fog lamps and to ground G102 and to the fog lamp switch turning ON the fog lamp indicator. The state of the fog lamps either ON or OFF will remain the same until the front fog lamp switch is pressed again, or the ignition switch is cycled OFF and ON. The park lamps or low beam headlights must be ON in order for the fog lights to be illuminated. Fog lamp operation will be cancelled whenever the park lamps are turned OFF or when the high beam headlights are selected.

 

OK it's worse still,

Now my fog lights, left headlight, and left parking light are out. Replaced all but parking light. Also, nothing lights up when I click the unlock button. This sucks!

Greg

 

If nothing lights up with the unlock button, check/replace your #2 underhood fuse.

Your foglight bulbs probably burned out completely, the wimpy 35w halogen bulbs have a very tiny and fragile filimant that fails easily. 55w bulbs have a larger filimant and HID kits like the one i offer have a 3000+ hour lifespan

Headlights burning out is routine maintence. You can expect them to fail after about 1000 hours of use (roughly 2-3 years of regular driving)

The parking light failure is a result of poor design on GM's part. The 3157 bulb is mounted so close to the plastic of the housing it will melt through the top. When moisture gets into the housing, this causes the bulb to explode. The most common fix it purchasing new corner light housings and using an LED bulb (burns cool to the touch)

Good luck.

 

Problem Solved (mostly)!!

Thanks radioflyer, I replaced fuse #2 (accessories) under the hood even though it looked good. Then I started the car and the BCM started to click incessantly for 5 seconds, and then my fog lights worked and my left parking light is also working. (As for my left headlight, that had stopped working because I had pulled that fuse by accident). So now every light is working.

I think pulling fuse #2 must have caused the BCM to reset (?), not sure. I also still lack any lights upon hitting the unlock button on my fob. I'll run it a few times before worrying. At least now I can get my inspection passed, and didn't have to pay $170 to a dealer!

Thanks again.
Greg

 

Light on lock/unlock might be turned off.

turn the key and press "options" on the DIC buttons until you see lock/arm. hit "reset" until you have it set the way you want, then test.

I'm curious if fogs are a requirement for inspection in PA.

 

Thanks for the tip. I went out to the car to try out your tip, and now everything is working perfectly. I hit the unlock button and all the lights come on. I guess the computer reset itself or something.

I share your curiousity about requiring the fog lights in PA. The dealership said they must work because they are on the car, not sure I agree with that logic.

Time to go for a drive!

Greg