2007 GMC Sierra Repair Question
How to troubleshoot dead horn...
Answer
What i would do is find the dark green wire that comes out of the fuse box that splits into to feeds.With the horn pushed and fuse in make sure both wires have a feed only when pushing the horn button.I know you jumpered power to the wire but this will sure you have the correct wires and there is power going thru them.If thats good you will have to make sure there is power at the horns and both horns have a good ground of 2 ohms or less to ground.Its easier to make sure the power is coming out of both wires from the fuse box and that its not making it to the horns or the grounds are messed up.Then tracing the power feeds to the horns because you assumed that was the problem and it wasnt.I learned to never assume anything when tracing down a electricial problem.
OK thanks saturntech9. If I can get to the crazy thing, I'll do that. I just can't believe how impossible these horns are to get to. It looks like I may hae to take the grill and fenderwell of to get the headlight out to get to the horn!!!! What the heck?
It says you have to remove loosen the front bump fasica trim cap.You dont have to remove the other things.