Steering Column Ground

[ScubaSteve]

Ok. And you are sticking the clip on the black wire into one of the bolt holes?

Yep the ground is plugged into the bolt hole. I just installed a new switch assembly and still no luck. The steering shaft has no connection to ground. The outside of the steering column has a good ground it just never get to the shaft. I needed the switch replaced anyway so nothing lost on that but I don’t know where to go next. I see some info on the older trucks having a jumper wire around the rag joint to make connections did the 86 models have anything like this?

[Gary Lewis]

Yep the ground is plugged into the bolt hole. I just installed a new switch assembly and still no luck. The steering shaft has no connection to ground. The outside of the steering column has a good ground it just never get to the shaft. I needed the switch replaced anyway so nothing lost on that but I don’t know where to go next. I see some info on the older trucks having a jumper wire around the rag joint to make connections did the 86 models have anything like this?

No, they didn't have anything on the rag joint.

If it was me, I'd test by pulling the two Phillips screws to take the horn pad off. Then I'd use a jumper from the black wire, after pulling it out of the threaded hole, to a known ground. And leave the other two wires connected. See if the horn works then with the key off and with it on.

That basically bypasses the ground wire to the brush, the brush itself, and the slip ring in the wheel. If it works then you know the problem is in that ground circuit. If not, it is elsewhere.

Meanwhile I'll see if I can figure out how/where the ground wire is. But I already know that the true wiring diagrams don't help - they don't even show the slip rings and brushes.

[ScubaSteve]

No, they didn't have anything on the rag joint.

If it was me, I'd test by pulling the two Phillips screws to take the horn pad off. Then I'd use a jumper from the black wire, after pulling it out of the threaded hole, to a known ground. And leave the other two wires connected. See if the horn works then with the key off and with it on.

That basically bypasses the ground wire to the brush, the brush itself, and the slip ring in the wheel. If it works then you know the problem is in that ground circuit. If not, it is elsewhere.

Meanwhile I'll see if I can figure out how/where the ground wire is. But I already know that the true wiring diagrams don't help - they don't even show the slip rings and brushes.

Jumping the black wire to a good ground the horn works key on or off. I am trying my best to keep from mounting a horn button on the dash or steering column but I'm getting to that point. Thanks again for all your time.

[Gary Lewis]

Jumping the black wire to a good ground the horn works key on or off. I am trying my best to keep from mounting a horn button on the dash or steering column but I'm getting to that point. Thanks again for all your time.

Ok, we are making progress. Now to find out why that brush isn't grounded......

Welcome.

[85lebaront2]

Bill - Yes, the horn relay was only used with a speed control, and actually mounted on the speed control's electronics. And, check pages 108 & 135 of your '86 EVTM for the horn with and without a relay. (At least unless when I scanned your EVTM I somehow added that info. )

As for three brushes, here's my spare column, with the one circled in red being the ground, the one in yellow being power, and the one in blue going to the speed control.

The one nearest the shaft is not a brush, it is the pin for the turn signal cancel cam, it goes into a slot on the bottom side of the wheel hub, the only brushes I have ever seen are the pair you have one with yellow/blue, the other with blue. Even the 1996 F350 column only uses two brushes, ground is the hub of the steering wheel.

I don't remember on the old column, but the newer columns and my Chrysler have a ground tab at one of the mounting bolts (the Chrysler also has a horn ground wire).

[Steve83]

The one nearest the shaft is not a brush, it is the pin for the turn signal cancel cam...

I agree.

I don't remember specifically because it's been so long since I used that column & cruise system, but I think the steering shaft grounded either through the column's top bearing (near the wheel) or the rag joint (which should have steel mesh embedded in the rag). I might still have one of those old columns here to check, but I doubt I have that kind of rag joint.

In the meantime, read this caption & follow the links:

http://supermotors.net/getfile/491917/thumbnail/cruisetroubleshooting.jpg

[Gary Lewis]

The one nearest the shaft is not a brush, it is the pin for the turn signal cancel cam...

I agree.

I don't remember specifically because it's been so long since I used that column & cruise system, but I think the steering shaft grounded either through the column's top bearing (near the wheel) or the rag joint (which should have steel mesh embedded in the rag). I might still have one of those old columns here to check, but I doubt I have that kind of rag joint.

In the meantime, read this caption & follow the links:

http://supermotors.net/getfile/491917/thumbnail/cruisetroubleshooting.jpg

Ok, I WAS WRONG! What I thought was the ground brush is, indeed, the pin for the turn signal cancel cam. And ground goes through the hub of the steering wheel.

Now, for my findings with chasing the ground on my two spare columns. One of them does not have connectivity from the shaft to anything. But, I do get a capacitor effect when I try to check for connectivity from it to the mounting bracket, which tells me that there are surfaces that are probably quite close but not touching or have a very high impedance between them, like grease. However, I don't get the capacitor effect on any other surface, nor on any of the wires coming from the column.

On the other column, the one from Dad's truck, there is connectivity from the hub of the steering wheel to the aluminum mounting bracket - most of the time. But if I move the wheel just right I lose the connectivity and get the capacitor effect. And, when I have connectivity to the mounting bracket there's no connectivity to anything else, like the ignition switch, its mounts, or any of its terminals. Nor the wires coming out of the column, nor to the mount that goes to the firewall or the rag joint or lower shaft.

So, I surmise that the ground goes through the aluminum mounting bracket. And it must go through the upper bearing, like Steve suggested.

ScubaSteve - Do you use the speed control? If not, you could make a slight wiring change and the horn should work properly.

[ScubaSteve]

Ok, I WAS WRONG! What I thought was the ground brush is, indeed, the pin for the turn signal cancel cam. And ground goes through the hub of the steering wheel.

Now, for my findings with chasing the ground on my two spare columns. One of them does not have connectivity from the shaft to anything. But, I do get a capacitor effect when I try to check for connectivity from it to the mounting bracket, which tells me that there are surfaces that are probably quite close but not touching or have a very high impedance between them, like grease. However, I don't get the capacitor effect on any other surface, nor on any of the wires coming from the column.

On the other column, the one from Dad's truck, there is connectivity from the hub of the steering wheel to the aluminum mounting bracket - most of the time. But if I move the wheel just right I lose the connectivity and get the capacitor effect. And, when I have connectivity to the mounting bracket there's no connectivity to anything else, like the ignition switch, its mounts, or any of its terminals. Nor the wires coming out of the column, nor to the mount that goes to the firewall or the rag joint or lower shaft.

So, I surmise that the ground goes through the aluminum mounting bracket. And it must go through the upper bearing, like Steve suggested.

ScubaSteve - Do you use the speed control? If not, you could make a slight wiring change and the horn should work properly.

I never used the speed control on this truck but only because it never worked. I think I will add a ground wire to the rag joint and see how that works out.

Thanks a bunch for all the help. I’ll keep you posted on the progress.

[Gary Lewis]

I never used the speed control on this truck but only because it never worked. I think I will add a ground wire to the rag joint and see how that works out.

Thanks a bunch for all the help. I’ll keep you posted on the progress.

You'll have to have a wire that will wrap around the rag joint. But it might work.

And my other idea will work if you want to explore it. Just requires you to pull the light blue/black wire out of the connector on the pigtail coming out of the steering column and placing a light bulb on it to ground. (Don't take it directly to ground.) The current going through it will be enough to pull the horn relay in.

And, if you decide to fix the speed control you can put the wire back in the connector.

[85lebaront2]

The one nearest the shaft is not a brush, it is the pin for the turn signal cancel cam...

I agree.

I don't remember specifically because it's been so long since I used that column & cruise system, but I think the steering shaft grounded either through the column's top bearing (near the wheel) or the rag joint (which should have steel mesh embedded in the rag). I might still have one of those old columns here to check, but I doubt I have that kind of rag joint.

In the meantime, read this caption & follow the links:

http://supermotors.net/getfile/491917/thumbnail/cruisetroubleshooting.jpg

I actually have a tester for the vacuum speed control, my son used it to test the one on his 86 and I used it to test the one on my 1994 Taurus.