The Dodge Challenger Message Board

Just got my new Rimblow wheel,(see photo), but after installing it, it dont work. Did some investigating, found horn relay missing from fuse box. Did all 1971 Challengers have the horn relay plug into the fuse box? The Year One catalog says the horn relay should be under the dash by the left kick panel on 70 and 71s and it also says that 70 model relays mount to the fuse panel.??? Anyway, I got the new relay and plugged in to the fuse box, but still no horn, allthough now I here a clicking noise coming from the relay when I squeeze the rimblow, and after awhile of tracing wires and testing, I went to remove the relay and it was super hot! Damn near burned my hand getting it out! What the &%$# is going on here? I did test the voltage at the horns and there is none when you squeeze the rimblow, so I figure the horns are Ok, but somethings up with the fuse panel or relay. This car did have the under dash wire harness replaced a couple of years ago before I got the car, it is a M&H wire harness. Could it have the wrong one? Any Mopar electrical engineers out there?

Well, pressing the horn ring completes the circuit,(ground). Are you sure the relay you used is in the right cavity. Did you run a jumper wire and test the horn to make sure it works?

The relay can only go in one way, but why was it overheating? I will try the jumper wire next, thanks Eddie.

My 1970 horn relay was just under the bottom edge of the dash in the far right corner.

It sounds like your relay is getting current full time.

If I remember right there should be a live from the relay to the horn that is only live when the relay is activated. So on the output from the relay you should have one live contact from the fuse box and one that when switched connects to the horns.

On the coil side of the relay you should have one lie connection and the other side of the coil should ground through the horn switch on the steering wheel.

The horns themselves need to the grounded through their mountings.

I think I got more problems than it looks, I tested continuity from the firewall connection ( Green wire w/red tracer)to the horns and I got none. looks like I'm going to have to rip and tear, I'll let you know what comes of it. Thanks Dave.

How many volts are you getting after the relay? It should be at least 12 volts all the time, before it should be zero volts. Did the horn work before you replacing the wheel?

No, the horns did not work when I got the car, but I found out they were not grounded properly, which I corrected yesterday. I now can use a jumper wire and get each horn to work. I am tracing the wiring from the horns back to the firewall connector, then to the relay, then to the horn switch. I keep you posted Eddie, Thanks !

The rotating connection at the wheel is a weak link and can cause problems.

I can see that, I took the collar off and the round copper contact dont look good. I suppose replacements are available. I might as well replace these wear items while I got it apart and save aggravation later. I think I am going to replace the ignition switch also. Any other problem childs inside the column?

Just cleaning the contact areas might work to test for a fault.

i lightly sanded my brass horn ring contact to get a better conection and it worked out for me. since you have your column apart check if the white plastic turn signal cam unit with hazard is OK. if not replace that too.

Something new happened, I put the steering wheel back on, started and moved the car, just decided to plug in the horn relay, and lo and behold,the horns started blowing, and kept blowing until I took out the relay, what gives?

Dana, are you sure the wire from the horn contact ring isnt caught on something, or torn to where it's grounding out the circuit, turning the horns on. It seems you have a short to ground somewhere along the steering wheel to the harness under the steering column to the relay itself. Did you check the fuse block to make sure it's not melted or damaged at the relay plug in point. 3 wires go to the relay the feed,(Dk. Green), the ground(black with tracer colour), the horn,(violet), it would seem to have to be on the ground side after the relay thats causing the problem.

I finally figured it out !! The problem was at the wiring connector at the firewall bulkhead, The green w/red wire was not making contact at the firewall where the engine harness plugs into the bulkhead connector. All is Ok now, except the new rimblow wheel has a bad switch, when I plug the wire from the steering column to the rimblow switch on the wheel, the horn blows and I can not get it to quit. I will be in contact with the guy I got the wheel from. It should be a simple fix. Thanks everyone.