Switch is momentary. You shouldn't need a wiring diagram...everything you need to know is in the first half dozen messages of this thread. The question is, whether or not there is a factory plug/wire awaiting you behind the pop out switch panel.
If not, you're gonna have to wire the whole thing yourself anyway....the BCM won't be a factor... and btw, the fog light indicator light on the instrument panel will not light up when the lights are on if you don't have the BCM reprogrammed...whether you have the factory wiring diagram or not.
On factory installs, the switch sends a momentary signal to the BCM, which then sends a signal to the relay, which turns on the lights. The BCM also sends a signal to the instrument panel indicator light and turns it on.

 

Thanks, I ordered the factory switch and relay from a very helpful Cadillac dealer in NJ. I got them both for about $20. I will use the switch either way. My car is too new to be in the GM system yet. There is a factory harness that we believe plugs into the PCM and runs down to the F/L that I will buy if the switch side is prewired. If it’s not then I will hard wire the switch to a 12 volt latching relay (we use these at work). These are rated at 30 amps on the relay side with a 12 volt control coil, this should be plenty if I need to go that route. I still need to know how to pop off the panel to get to the switch. Thanks again Curmudgeon for your reply.

 

The panel known as the waterfalls which covers the radio, and all the controls, just pops straight out. I'm looking for the thread that has the pictures but if any one else can find the thr first, please post.
Here you go. http://www.socalhhr.citymax.com/hhrradioremoval.html

 

Thanks an08HHR. The panel came straight out by pulling at the A/C vents. I found a three wire connector (ORANGE, GREY and BLACK/with a WHITE tracer). I believe that will be for the fog lamp switch. Just have to wait now for the stuff to get here. Paul (1-908-561-2900 EXT 1137), the NJ Cadillac dealer parts guy, is very helpful in in finding and ordering the correct OEM parts. Once I get it all together I plan to have the dealer reset BCM to see if it will work.

 

All you need is a single wire from the relay in the fuse box to the lights themselves. Of course it will need to "Y" so there is one hot wire to each light. You then ground the light to any bolt on the frame near it.
The hardest part is getting the wire into the output leg of the relay...but it ain't a huge/hard deal. Can't see why you'd pay for a "factory wire" when it's so simple to do yourself.

Curmudgeon

 

Hi all. I got everything now. I got the factory switch installed and wired. I have the harness built. I have not figured out how to get the power distribution box apart to get the wire connected to the factory realy . I did find the correct size spade connectors that fit the legs on the relay. I have searched the threads but I could not find any instructions for taking the PD box apart. I am encouraged, pressing the fog lamp switch turns on the insturment panel lights (not the fog light indicator, yet) so once it is all installed I am confident that resetting the BCM will cause them to work as the OEM setups.

 

Me again. I have installed the lights and the factory switch. I have the wires running up to the under hood fuse box. Mine is an 08 and did not come with the fuse and relay installed (I have those installed as well). I have removed the fuse box from all of the connectors (harnesses). I don't have a clue as to where to connect the wire. On mine it looks like the wire will need to be inserted into one of those connectors. I have the correct size spade connector to do this but I just don't know where to insert it. Please send a picture if you can help.

 

the conector location in the wirring diagrams are unclear about the concetor on the bcm so I added my own. it is the conector at the lowest point of the bcm the bcm is located with the inside fuse box. hope this helps.

since I'm new to posting pics if this doesn't work go to gallery and type fog lights install and it "should" bring up the pictures.


*** Sorry not all the pics came over with the post so you will have to go to the gallery and search.

 

Hello,
Anyone have a part number for the female spade connector under the hood in the relay block to run the wires to the fog lites? The number in earlyer post is no longer good.

I pulled one from a 2002 GM Car at the juck yard only to find it wouldnt fit. Dealer said they changed over the design in 2005. (I wont be finding any of them in the JY).

I find it quite funny that this part has been around that long and all the local dealers cant find it in thier parts manual. They said " I can sell you the enitre harness?"

Thank you,
Craig~

 

I was able to get the conectors for the body controller but the conectors for the under hood fuse box are not serviced. I used after market conectors form local part store. you can find a asortment pack that will have the corrcet size in it then I just pushed it up in to the factory harness connector. it won't lock in place but it fits sold on to the spade.