Horn issues

[chillman88]

Just changed out the steering column AGAIN. It's pretty bad how efficient I've gotten at that job. New column is lower mileage and in much better shape so it should last pretty well.

Now my horn works again! Only with the key off... What the....

My truck came with a tilt wheel and cruise control.

My horn USED to work fine. Swapped in a FIXED NON-CRUISE column, no horn. Swapped my cruise wheel horn over and the horn worked! (Once...) The truck the column came from had a button on the dash for the horn so I didn't think anything of it, figured it was a pre-existing condition.

Now another fixed column with my cruise wheel horn on it and the horn works fine if the key is OFF. Nothing to do with running or not, just turning the key on the horn won't work.

I'm thinking grounding issue? Anyone have any idea? I'm stumped.

Edit: These are for an 86. I'm blindly assuming they are the same...

You must be registered for see images attach

You must be registered for see images attach

 

[Thewespaul]

What I do with horn issues is use a test light clipped to the output of the horn switch to see if the column is an issue. Take a drive around and occasionally honk the horn while turning and driving over uneven ground, the test light should light up whenever you honk the horn, if it doesn’t then you know it’s a power supply issue in the column, which is usually poor connections within the switch.

 

[laserjock]

Horn runs through the cruise module on a tilt cruise truck. It just goes to the relay on a non-tilt cruise truck. I think your mixture of bits may be the issue. You may be able to put the cruise wire harness in the non-cruise column and make it work.

 

[chillman88]

I thought about that but it didn't work at all with the non-cruise horn but it does with the cruise horn.... With the ignition off...

 

[laserjock]

I thought about that but it didn't work at all with the non-cruise horn but it does with the cruise horn.... With the ignition off...

Remind me tomorrow I’ll post the diagrams for 91. I also seem to remember that the cruise and non use different horn relays. If I remember right, a non cruise horn pad switches differently than the cruise one. The cruise one basically uses both legs that the non cruise uses for signal to the box via resistances grounded to the steering shaft. The basic horn pad just contacts the two wires. Does that make sense?

 

[chillman88]

Sounds right based on what I saw swapping them. That's why I'm thinking it's a ground issue... But I don't know WHY. It doesn't make sense... I'll tag you next year

 

[chillman88]

Remind me tomorrow I’ll post the diagrams for 91

 

[laserjock]

You must be registered for see images attach

You must be registered for see images attach

This help?

 

[chillman88]

This help

Well... Yes... And no.

After looking at it for far longer than should be necessary... It seems to confirm my theory.

The only difference between the two is the actual horn pad wiring and the relay (as far as the horn is concerned).

Cruise trucks: Horn "button" provodes a ground for the horn relay. Horn relay connects the power to the horn circuit.

Non cruise trucks the horn "button" connects the power to the horn.

Therefore basically confirming that my issue SHOULD be insufficient ground when I have the vehicle in "run".

If the only difference is the horn pad and the relay, and I have both of the components from the original cruise setup that used to work, then a mismatch can't be the issue, and my problem must be something other than the switch wiring. Especially since it works fine with the truck off.

I'm going to ground the base of the column directly to the battery with jumper cables and see if that helps any.

 

[laserjock]

Is it your multifunction (turn signal) switch? Doesn’t it have like a little grounding wire in it for the column? Which turn signal switch are you using? Tilt and non are different.

 

[chillman88]

Is it your multifunction (turn signal) switch? Doesn’t it have like a little grounding wire in it for the column? Which turn signal switch are you using? Tilt and non are different.

THAT would be the issue then. I'm using a fixed column on a tilt truck...

BACK TO THE DIAGRAMS! lol thanks!

 

[chillman88]

Is it your multifunction (turn signal) switch? Doesn’t it have like a little grounding wire in it for the column? Which turn signal switch are you using? Tilt and non are different.

I'm not seeing anything in the wiring diagram to indicate there's a difference. I'm going to go out and conpare my tilt column with my fixed and see if I can tell. It's odd the diagram wouldn't show it though...

 

[chillman88]

I have compared two columns I have in the garage. A fixed column that the horn NEVER worked on, and a tilt column (from an 84 just to be clear) that the horn DID work on. Both were in my 91 at some point.

I see no difference in the actual connector for the multifunction switch. Both appear identical in wire count and wire color.

I'm heading out now to play with grounding tests.

 

[Thewespaul]

There’s no difference in the wiring diagrams between the tilt and non tilt column harnesses, although the turn signal switches are very different. Make sure the ground is good for the turn signal switch and then add a ground from the aluminum bracket to one of the 10mm bolts holding the gasket to the firewall and see if that makes a difference. Although the horn pads switch power vs ground in the different columns, it won’t matter for the horns function

 

[laserjock]

You must be registered for see images attach

You must be registered for see images attach

From my 83 manual but I believe it to be the same. If the ground cam is missing it may be grounding through the key in switch dodad that turns the door chime on. It would only be touching at certain positions of the switch I think??