Strange electrical issue.

[Partsguy61]

The brake switch has been replaced with an OEM unit. I get the message even with the brake switch harness disconnected from the switch.

 

[Rocket Man]

The brake switch has been replaced with an OEM unit. I get the message even with the brake switch harness disconnected from the switch.

Do you have led tail lights by chance?

 

[wjburken]

Probably your brake switch for both problems. If there’s any issues with the brakes or brake lights the CC won’t work.

^^^^^This^^^^^

 

[treehan77]

Just because you replaced a part, doesn’t mean it’s a good part. But you’d think you’d get a code when scanned (won’t turn on CEL) though for those. You can easily scan/or test the brake/stop switch.

 

[Partsguy61]

Do you have led tail lights by chance?

I do, but I have resisters installed and the cruise was working perfectly for many months after the LED tails were installed.

 

[Partsguy61]

Just because you replaced a part, doesn’t mean it’s a good part. But you’d think you’d get a code when scanned (won’t turn on CEL) though for those. You can easily scan/or test the brake/stop switch.

I have tried 2 new GM brake switches and the result is still the same.

 

[Partsguy61]

Ok, a recap of the whole thread. There are no stores codes. I have tried 2 new GM brake switches and neither fixed the problem. The cruise didn't just stop working completely one day, it worked less and less over a period of a couple of weeks until now it won't engage at all. I greatly appreciate all of the assistance you are providing, I really do and I don't want it to come across like I don't.

I work in the parts dept. of a Chevrolet dealership. The truck has been in the shop 3 times and the techs haven't been able to find anything, that's why I am reaching out to try and find someone who may have had a similar problem. Most of our techs are younger guys who aren't familiar with the older stuff and they aren't really thrilled when I bring the truck in for any diagnostics. LOL

 

[Fless]

Any chance of temporarily replacing the LED taillight fixtures with OE incandescents? Maybe the resistors have gone out of spec.

 

[Rocket Man]

I do, but I have resisters installed and the cruise was working perfectly for many months after the LED tails were installed.

Any chance of temporarily replacing the LED taillight fixtures with OE incandescents? Maybe the resistors have gone out of spec.

Exactly what I was going to say. Put regular tails in and I’ll bet the problem goes away. Are the load resistors on the brake light circuit or just the turn signals, for hyper flash? 99% of people who say they have load resistors on their led tail lights have them on the turn signals only. Also another thing I can verify- if you have LED’s in the brake lights and also installed load resistors on the brake light circuit, your CC will work as well as all your brake lights, that’s great right? But then if you add led bulbs in your front turn signal locations your main brake lights won’t work and only the third brake light will. That’s because the brake lights interrupt the rear turn signal circuit which is also the front turn signal circuit. There’s not enough resistance in the turn signal circuit so it keeps flashing and the brake light doesn’t illuminate. This happened on my 02 and I verified it by swapping incandescent bulbs into the front turns and the brake lights went back to working. I ended up having to add load resistors to the front turn signal circuits.

I highly suggest swapping regular incandescent bulbs or if your entire housings are led, stock housings with incandescent bulbs in the tail lights/ brake lights snd see if the problem persists. These trucks behave strangely when you start swapping leds in.

 

[Partsguy61]

I do have LEDs in the front turn signals and aftermarket LED housing assemblies in the rear. I have resisters on both the front and the rear as well. I do have my OEM tail lamp housings so I can swap those back in and see if that makes a difference. At this point I'm ready to try almost anything. Most of my driving to and from work is highway and I'd really like to have cruise control back. Thanks