My Cruise isn't working. It turns on, but will not set. The BCM has a p0571 stored. I'd swap out the brake light switch (if I could fine it) but my brake lights are working fine. I got to thinking, I have an LED 3rd brake light. It does have a resistor on it, but if the resistor was wrong or bad or the solder joint for it was no good would it throw this code?

Any ideas?

 

wasn't anything a soldering iron couldn't fix.

 

^^^ damn i love these posts when the poster posts the results. soon the poster wont post and we will never know.

life is good.

 

If I can save someone else a little frustration it's with the 5 minutes to post.

 

I've got some time today, so I fixed it properly and took pictures while I was at it.

The 3rd bake light LED kit comes with small spades at the end of the wires, not a plug. I guess you're supposed to stuff them into the factory hardness and tape them in or something. That doesn't work well. Electrical tape loosens up over time and then the wires lose contact and your BCM gets unhappy about that. You start getting the p0571 code and your cruse doesn't work.

I ran into this and fixed it for good.

I had as spare old bracket that holds the 3 bulbs so i didn't have to cut mine up, fortunately

http://www.flickr.com/photos/27492162@N03/8301648084/http://www.flickr.com/photos/27492162@N03/8301648084/It has the plug that'll fit the wiring harness.

http://www.flickr.com/photos/27492162@N03/8301647668/http://www.flickr.com/photos/27492162@N03/8301647668/
I broke out the Dremel and cut it loose.

http://www.flickr.com/photos/27492162@N03/8300593743/http://www.flickr.com/photos/27492162@N03/8300593743/
http://www.flickr.com/photos/27492162@N03/8301647112/http://www.flickr.com/photos/27492162@N03/8301647112/
I took my good housing with the LED board inside of it and extended the wires slightly because they are kind of short. Not too much, I didn't want to create a rat's nest inside the trunk, but I added a little wire to work with.

http://www.flickr.com/photos/27492162@N03/8301646964/http://www.flickr.com/photos/27492162@N03/8301646964/
http://www.flickr.com/photos/27492162@N03/8300593155/http://www.flickr.com/photos/27492162@N03/8300593155/
While I was at it, I took the time to make sure my hot glue mounting hadn't loosened. It was fine but I drilled a couple of holes and ran a wire tie around the board just to add an extra level of protection from it coming loose or moving.

http://www.flickr.com/photos/27492162@N03/8301646162/http://www.flickr.com/photos/27492162@N03/8301646162/Back to the wires, I put them into the plug. Then I used plastidip as it was actually meant to be used. I coated those shiny spots you see below. I don't use the spray. It's useless. I use the can with a small brush. Plastidip is actually really good for this work. It doesn't shrink like silicone and will keep those areas dry for years.

http://www.flickr.com/photos/27492162@N03/8300592853/http://www.flickr.com/photos/27492162@N03/8300592853/Next I used a liberal amount of electrical tape over the wires to keep them from chafing, or snagging. I used two tiny little zip ties, one on each end so that the tape wouldn't unwrap over time. The tape doesn't have to hold anything together, it just needs to add a layer of protection in case the wires rub under the trunk pad.

http://www.flickr.com/photos/27492162@N03/8300592305/http://www.flickr.com/photos/27492162@N03/8300592305/
I put the housing back on the trunk, plugged it in tested it all out. Cruise works again. I don't expect to ever have to touch this again except to reseal the housing to the slot in the trunk since I did remove it. The factory seal is pretty well junk so I use DAP rubberized marine seal, in black. It'll hold up to anything.

 

Hey, I have this third brake light sitting in my closet


Thanks for this post. I am getting the p0571 on my 09 LNF now. Dipshit previous owner shaved the third brake light in it and stuffed a license plate light bulb into the harness clip; it doesnt stay. I will be making a little bulb harness like you did for that bulb to clear this up.