my horn does not work. when i push the button i hear a clicking noise comming from the CPU. i replaced the CPU and the horn worked for 3 secconds then the same problem re occoured. any suggestions i dont just want to continue buying new CPU's

 

If the CPU is still "clicking" I'd assume the relay is still working, and all that's left is the pins and wires going to the horns, and the horns themselves. You could probably verify that the horn relay still works by unplugging the horns and measuring the voltage they'd see with and without the horn pushed. If it doesn't switch voltage as you'd expect, you could investigate further by opening the CPU and testing there. In my experience relays usually get stuck on, not off, so my guess is it's not the relay that's broken.

If you get switched voltage out of the CPU as you'd expect, that leaves the wiring harness and horns. You could test the voltage at the horns, and if that's switched, it's the horns or their grounds.

Also, it looks like there's a 20A fuse for the horns and brake lights, which you might check. My5ABaby came up with a list of fuses that should come in handy:
http://howto.globalvicinity.com/gv_w...i=93&co=1&vi=1

edit: while you're at it check if your charging system is overcharging.

 

When my horn didn't work, I pulled the CPU out and removed the circuit board that included the horn. It's the largest board in the CPU. Once I had it out I cleaned everything thoroughly with contact cleaner and that fixed the problem. I've also heard guys that actually desoldered and the resoldered the 15 or so contact pins to make it work. Before I did all that, I verified that the horn worked.

 

take some light gritt sandpaper and clean up the horn contacts and ground points. might help.

 

Nairb82 why did you bump. Did you do what everyone asked? Bumps are forbidden here in the 2nd gen technical section. Your bump has been deleted.

And when you said you replaced the CPU, did you replace the CPU with a new or used unit? If you replaced it with a used unit, that unit probably had the same issues.

To fix a used CPU you must remove the solder from the circuit board where the pins for the plug meet the board. Then flow new solder in.