Horn Not Working on PPV, My Diagnosis Thus Far (Actual Horn Unit Works)

[Bigcrow74]

I know it’s been 3 years since your horn issue write up but I’ve recently acquired a 2012 Tahoe PPV with same exact issue. What did you end of doing to resolve yours?

 

[Joeyhosmanole]

I know it’s been 3 years since your horn issue write up but I’ve recently acquired a 2012 Tahoe PPV with same exact issue. What did you end of doing to resolve yours?

Been awhile since I checked in here. You've probably already found a few similar issues and maybe some solutions.

But in case this is still eating at you or any one else; before these ppv/ssv trucks go into service they arrive at an upfitter from the factory where a whole bunch of splicing and rewiring occurs.

It is pretty simple in many cases to resolve issues like the horn, reverse lights, brake lights, rear door locks not working by locating where the upfitter spliced the wiring and restoring it back to the factory configuration by removing the splice.

Of course you'll want to check related fuses before getting tangled in wiring. If the fuse is bad, replace it first and try again. If the fuse is good, high likelihood that whatever function is inop was modified by the upfitter.

In the case of the horn, take a peek under the dash and gently poke around above the gas pedal for a brown wire, it may have some length to it and may be tucked away deep inside the dash or near where the center console would meet the dash. Some other members posted some helpful photos in this same thread to help with the horn.

Once you find it, simply follow the wire in each direction until you find where it has been spliced. It should appear obvious as if an after market splice was applied. Cut out the after market wiring and restore the factory wiring by reconnecting the 2 ends of the brown wires.

The same method may help you with the brake lights and reverse lights. Check the BCM which is to the left of the brake pedal. If you see any wires that appear as if an after market splice has been applied, cut out the splice and restore the original wiring by reconnecting the remaining ends. Just make sure that the colors match.

For the rear door locks, remove the door panels and find a spliced wire near where the speaker cavity is. Restore the factory wiring by cutting out the after market splice and reconnecting the remaining ends. Viola your locks work again.

As always please take proper precautions by disconnecting battery, etc. before tinkering with wiring.

 

[Darrius]

I found the horn wires. You said to get the reverse lights working it’s the same process but what color are the reverse light wires. Any idea why both my center and rear dome light are not working.

Thanks in advance.

 

[Sparksalot]

You guys are great, thank you!

View attachment 74483

This was super helpful. Mine wasn’t cut but, the tan and black (horn ring?) have identical connectors and were plugged in crossed. Switch them back and horn works now.

 

[hobstexas]

I am experiencing the same issue!

 

[WheelsOfSteel]

Even though this is an older thread I figured this would still be a good place to post. I have a 2012 Chevy Tahoe PPV and have been trying to sort out the horn not working. After reading through this thread I believe I found how to fix it but would like an opinion on this. I located the 6J4 Inline Connector as shown in the booklet photo under the center console. The two tan wires look alike and I believe it was cut and each one end was crimped into a black wire and a black and white striped wire as shown. I want to cut and reattach both tan wires but I am a bit apprehensive.

 

[WheelsOfSteel]

Even though this is an older thread I figured this would still be a good place to post. I have a 2012 Chevy Tahoe PPV and have been trying to sort out the horn not working. After reading through this thread I believe I found how to fix it but would like an opinion on this. I located the 6J4 Inline Connector as shown in the booklet photo under the center console. The two tan wires look alike and I believe it was cut and each one end was crimped into a black wire and a black and white striped wire as shown. I want to cut and reattach both tan wires but I am a bit apprehensive.

So I got over being chicken and cut the wires. As you can see I cut on the black wire sides in order to leave myself some extra wire length and stripped enough to test. I tested for continuity and power and only had power to one tan wire, and the other tan wire showed no continuity or power. I held each end together and pushed the horn and it worked. I then crimped the wires together with the blue connector. Hope this might help someone else.