M35a2 horn goes off when ever it wants

[tractorpuller1]

Hello.
My Deuce has a faulty horn. It goes off at random while driving. I almost scared two pretty girls off their bicycles and into the truck.
I stopped at my Dads farm to investigate. I pulled the rubber disc off, turned the plastic disk underneath counter clockwise and pulled it off. The brass coated spring and cups look fine. The black wire is nestled in the center of the steering wheel hub and has bakelite on the end with a steel half ball exposed. Touching the ball to the steel hub of the wheel sounds the horn. I cleaned the parts and reassembled. Now, no horn at all. I can not find where the horn wire comes out of the steering column. My eyes are not so good any more. Is there a short in the wire? Where does it come out? Where does it trigger the air horns. I can not drive this truck safely if it blasts off at random.

Any help would be very much appreciated.

Larry.

 

[sigo]

I think I have a similar issue with my M813. I was just moving it in my driveway awhile ago and the horn sounded. I thought maybe I just bumped the button with my arm, then it happened again. I'm pretty sure I didnt bump it again. I thought maybe it's just me, there's nothing in the TM about it. I'm curious as to what other folks have to say about it.

 

[AceHigh]

If I remember right the power goes to the horn then up the wire to the button. When you push the button all you are doing is grounding the circuit to complete it, then it honks.

If the wire makes contact anywhere along the path it is the same as pushing the button.

 

[barefootin]

The wire comes out at the front of the steering gear (box). It's a single wire and it may be chaffing by it's retention point on the frame or at the exit of the box. The insulation was cracked and strands were showing on mine right where it exited the steering gear. I degreased it with electrical contact cleaner and re-coated it with liquid electrical tape (tool handle dip works as well).

 

[steelandcanvas]

This may help. The wire comes out of the steering box, through a little grommet. Usually the wire is chaffed inside the steering column, causing it to short and sounding the horn.

 

[Tow4]

As mentioned above, the horn button does complete the circuit by grounding the wire going into the steering box. If it's not chaffed where the wire comes out of the steering box, follow the wire until you find it. It could be near the valve at the horns too. There's a connector where the wire comes out of the steering box you can disconnect and put your ohm meter between that wire and ground (the steering box, make sure you have a good connection) and check for a short in the column.

 

[SMOKEWAGON66]

Randomly honks eh? Thats kinda funny. I saw this vid of these college kids or something, who played a trick on their friend. They hooked the horn in his little car up to the brake pedal, so everytime he braked, the horn would honk...it was hilarious.

On my truck, I disconnected the original meep meep horn and installed a loud SOB of an airhorn and added a button valve to the dashboard so my steering wheel button is useless...I kind of like it that way but thats just me.

 

[kcollum]

When I got my truck home it had Romex from the horn button to rubber retaining plug at the base of the steering box, good old Gov fix. It would short out inside of the steering column and sound the horn. Or it also could be any were along the wire to the horn solenoid.

 

[tractorpuller1]

Thanks.
I'll try tracing that wire.

 

[tractorpuller1]

Ok.
I think I got it. The horn button has a small cup, a spring, then a large cup for contact to the steering hub, right? When I took it apart, very carefully, I found, the spring, then the small cup inside the large cup. The small cup was visible through the hole in the large cup.
Now, I have the indent of the small cup over the center of the horn wire, THEN the spring, THEN the large cup. I think they had it wrong. It can go together either way. The horn wire can inch up and wander the other way.
I think I got it.
However the the wire at the bottom of the grommet at the end of the steering gear is worn, so I pulled the exposed wire into the grommet a little more to cover the worn section.
Keeping my fingers crossed.
Thanks every one!

 

[caliber1]

Slather the wire that comes out of the steering box with some liquid electrical tape, and maybe slide some split loom up on there and secure in place. Mine was worn through there, and by the horn.

 

[kcollum]

Saturn has a replacement horn wire for $6.50 M35 Horn Button Wire Lead XH-2667 5995-00-752-1492. I used this to replace mine, just use the old wire to pull the new in.

 

[Motorcar]

Old thread but comes up in the search topic, mine started doing the same after 7 years of ownership. Pulled the steering wheel button apart and found the wire had come out of the connector under the contact. Just bouncing down the road it would honk anytime that wire touched ground inside the column. Pull a quarter inch wire up through the steering column and gearbox, trim, solder a new bullet connector on, re-install. Will outlive me I imagine.