On older vehicles there was a wire going through the clock spring's ribbon cable for each switch, but there weren't very many switches. When they added a dozen switches for everything but an electric chicken plucker, it became impractical to have that many wires. Instead, each switch develops a variable voltage, and all of those are sent on a single wire. One of the computers interprets each voltage as the request signal for what that switch is for. To answer your question, yes, you can have a single defective switch while all the others work fine.
I haven't worked on a horn problem yet on a vehicle as new as yours, but Chrysler did have a big problem on older trucks starting in the late '90s. The horn switches were built into the steering wheel air bag's cover, and caused a lot of dead horns. The switches worked if you pressed them really hard. The fix was to replace the air bag assembly.
There also was a problem on some trucks where the bolt holding the horns broke, then the horns would fall off, and all you'd be left with was a pair of wires hanging down. Another common problem was one of the two horns would short, and that would cause the fuse to blow. If the vehicle was still under warranty, we had to determine which one needed to be replaced, and use one supplied by Chrysler. For vehicles out of warranty, it was less expensive for the customer if we used a universal replacement horn.
Given the variety of things that can cause a dead horn, the best approach is to use a scanner to access the Body Computer, and / or the Integrated Power Module, (under-hood fuse box)), to command it to activate the horn. The scanner will also list the horn switch as "off" or "on". If you see it change when you press the switch, you know that part of the circuit is working.
Another clue is if the horn chirp works when you lock the doors with the remote, (if that option is turned on). If you hear that chirp, you know the horns and fuse are okay.
Friday, July 28th, 2017 AT 9:17 PM
