Electrical, one I haven't seen.

[lonesouth]

So, we've done two things to the electrical since the bronco last ran without issue.

1. We added the explorer serp setup with 4g alternator. Red/Green wire from the voltage regulator to the alternator red/green, charge lug to positive battery side of the starting solenoid.

2. Installed a grant steering wheel.

The first thing that told me something was wrong, when we hooked up the battery, the horn was stuck on. I'm guessing it has to do with my grant steering wheel install.

The second thing I noticed tonight. With the engine running, when I turn the wheel ~20 degrees off center, I can see sparks between the shift collar and steering wheel. In addition, the whole electrical system seems to short out when I get the sparks. Radio shuts off, lights shut off, but the ignition is still powered. The radio is powered off a relay that is signaled from the I terminal of the starting solenoid.

Oh, and the short apparently also prevented the key from activating the starter. I'm guessing the horn is shorting the I terminal to ground, effectively shutting down all of the electrical items. Does this even make sense? It doesn't do anything in ACC or ON, only with the engine running.

 

[rustbucket]

Pull the steering wheel and see where it shorts.

 

[lonesouth]

Steering wheel shorts at about 2 o'clock. Also forgot to mention we disconnected the horn relay when we installed the battery and the horn stayed on.

 

[rustbucket]

Could the turn signal or tail light wire be shorting to the horn?

Edit: Probably not tail lights, unless you had the light switch on. I'm thinking maybe the the turn signal positive.

 

[broncnaz]

Sounds like something is back feeding to the horn not sure how the horn would stay on when you disconnected the relay unless you disconnected the wrong relay or the relay has been bypassed somewhere else.

 

[El Kabong]

Some of the Grant horn buttons (Signature Series at least) have a spring wire that needs to be cut off before installing on our trucks. It is needed for a 1 wire horn, but shorts out on a 2 wire horn if it's not cut off. Since you didn't mention it, I wonder if that step might have been missed.

Here's a link to one of their installation sheets. See the second half of step 3. http://www.grantproducts.com/files/instructions/97551-00-01.pdf

 

[DirtDonk]

Holy cow lonesouth. Time to pull the wheel off and find out what's going on.
If you see sparks, it's time to get busy. And since you can't drive without turning the wheel, which causes more sparks and loss of power to other accessories, you have a problem that should stop you from driving it until you fix it.
You could even be living on borrowed time before something melts down in spectacular fashion. I'm not sure why your issue is shutting down almost the whole truck, but that's just another sign of potentially impending doom. If you can get circuits in the steering column to shut off the engine and keep the starter from engaging, it's more than just a shorted out horn button.

And take the radio relay wire off of the ignition circuit.
I suppose if you haven't had any trouble with it in the past, it's working fine. And using a relay is probably helping, but I sure hate the idea of something sharing the circuit with the ignition.
Are you running points or Duraspark? Since you have a relay, it's assumed that you have a later EB of late-'73 or later vintage?
There are other, more appropriate circuits to feed from.

There may be a way to re-orient the wires in the steering column plug so you don't have power to the wrong place, but that's going to take a lot of patient poking and prodding with a volt-ohm meter and may not work anyway, if the wheel adapter is set up incorrectly.
Better to take the wheel off now and see if it's simply an incompatibility issue with your column. Which is exactly what it sounds like. Besides, how long could it take to remove the wheel for inspection, compared to tracing wires under the dash while standing on your head?

At the least, put the old wheel back on until you figure it out.

Paul

 

[lonesouth]

Good points Paul. As I was reading your post, I remembered that I took the power signal from the center post of the ignition switch. This was the first time I've driven it at night, and there really aren't that many electrical systems in my bronco, so I had not noticed it before. The lights going on and off, and visibly seeing the sparks is how I discovered the problem. To clarify, the engine kept running, but all of the electrical systems shut down. I am running Duraspark.

I don't recall anything like the spring in the grant wheel. I'm going to pull the wheel when I get a chance and sort out the horn wiring. I'm not too keen on the grant wheel design, so I'll probably just disconnect the horn circuit altogether. And don't worry, I'll not be driving it till I get it sorted out.

On the plus side, all of my lights work except the rear driver's side marker. Oh and the gauge light was on at one point, but off most of the ride home. Even the gear indicator on the column was dimly lit.

 

[oleguy74]

never attach anything to I term on solenoid.that goes directly to your ign.whether in start or run that has power for ign.

 

[DirtDonk]

Ok, cool. So the radio relay should not be a problem then, if powered from center post of the switch. Whew! Now I can chill out a bit.

Good to know that the engine didn't cut out too. Makes things seem less dire. Well, sparks are still dire, but not quite as dire. ;D

Generally, the only lights that would be effected by a fault in the steering column would be the brake lights, turn signals, and hazards. But since there is also that single Blue w/red wire for the PRNDL light, it could theoretically mess with the other dash lights in the circuit.
Not sure why a side marker light would be effected though. Perhaps just a side issue with that light by itself. Probably.

Get the horn sorted out then, and everything else will most likely fall into place. With the later relay style, you only have the Blue w/yellow wire to switch to ground to activate the horn relay. If the button/adapter is grounding it all the time, there's one problem you can solve. If it's grounding it to something else, that's likely your sparkage.

Good luck. Let us know what you find when you dig into it.

Paul

 

[lonesouth]

So, I took the steering wheel off and didn't learn much. What I did find is about 1 volt between the steering shaft and the column. This is with the ignition in on. Tomorrow I'll see what the voltage is with the engine running. Looks like its time to rebuild my tilt column and just be done with it.

 

[lonesouth]

So, the ground strap between the body and the frame has corroded in two. I suspect the column was making the connection through the steering shaft.