Gents - I have a 2000 UJZ100. Recently the horn began to sound as I pulled out onto the road after picking up my girlfriend. No amount of turning the ignition on and off or pushing the remote entry button on the key had any effect. I pulled the horn relay and we went on our way. The next day, I reinstalled the horn relay and all was well. Yesterday, at the carwash, on the way to pick up my girlfriend. The horn began to sound again. Again, no joy with the key. Pulled the relay and, on re-installing it today, it's back to normal. My question is this: should I get a new girlfriend?
Well no. That isn't the question. Pretty happy with this one, actually. Looking at the wiring diagram, it appears the horn relay is pulled to ground by two things: the steering wheel horn button and pin 12 on the Theft Deterrent ECU. I think it's less likely that the horn switch is intermittent than there's something going on in the anti-theft system. I'm curious about a couple of things:
1) does anyone know where in the vehicle the ECU pin 12 wire connects to the horn switch wire? The parts location diagram seems to place it behind the dash, which would make it a pain in the butt to isolate.
2) does anyone have troubleshooting notes on the Theft Deterrent ECU? If I assume for a moment that this ECU is the issue, what conditions would cause it to sound the horn, while still allowing the vehicle to start?
Well no. That isn't the question. Pretty happy with this one, actually. Looking at the wiring diagram, it appears the horn relay is pulled to ground by two things: the steering wheel horn button and pin 12 on the Theft Deterrent ECU. I think it's less likely that the horn switch is intermittent than there's something going on in the anti-theft system. I'm curious about a couple of things:
1) does anyone know where in the vehicle the ECU pin 12 wire connects to the horn switch wire? The parts location diagram seems to place it behind the dash, which would make it a pain in the butt to isolate.
2) does anyone have troubleshooting notes on the Theft Deterrent ECU? If I assume for a moment that this ECU is the issue, what conditions would cause it to sound the horn, while still allowing the vehicle to start?