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Old 12-04-2011, 01:02 PM
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more electrical problems

Well, I managed to get the new turn signal switch installed and now have functioning hazards and turn signals, so onto the next issue, no instrument panel lights, the turn signal indicator lights do light up in the cluster though, i have found the headlight switch needs replaced since theres no power feeding from it to the cluster, which brings me to my first question.

Does the HIGH beam indicator light receive its power from the same wire that feeds the printed circuit off the headlight switch?


question 2:
Horn....if i push the horn button i get nothing, no sound, no click in the relay(new relay), nada......there is power to the relay, although i did find out by accident with a test ligh that the horn works, while probing the relay i touched the back single contact, with the test light on the neg. bat terminal and the horn blew, so the horn works for the relay but not from the horn button, would this be where it needs grounded through the rag joint(which needs replaced anyway), steering wheel is and aftermarket grant wheel with the install kit, so all that is new.

thanks for the help
 
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Old 12-04-2011, 01:57 PM
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Power to the high beam indicator comes from the dimmer switch on the floor, not directly from the headlight switch. Power to the instrument cluster illumination is a separate circuit.

Before replacing the headlight switch, make sure the dimmer is not turned all the way down, and that the fuse is good.
 
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Old 12-04-2011, 02:03 PM
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I checked fuses, have power there but none coming out from the headlight switch, so for a few bucks, i'll just put a new one in......

what would be the route to check the high beam indicator light though? the switch works to turn high beams on and off, just no indicator light in dash, which i wouldnt care, but its an inspection requirement.
 
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Old 12-04-2011, 03:34 PM
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Check the bulb itself first. If it's OK, then remove the cluster and inspect the back. The cluster is made out of a composite material that crumbles apart with heat and age. The bulbs are held in by small locking carriages. It's somewhat common for the cluster to break apart where the bulbs lock into place, making them lose contact.
 
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Old 12-04-2011, 06:38 PM
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Thanks FMC, I did forget to look at the actual bulb, althouch i did clean all the contacts on the bulb holders and the printed circuit.

I also replaced the cluster already with one from bronco graveyard, due to the original crumbling, but its still not a newer one, so eventually i'll have to do it again i'm sure.


anyone have any ideas about the horn, that one is bugging me too, cant figure why it works FROM the relay, when the relay is getting power, which comes from the harness that the signal switch is on doesn't it? again it has a grant wheel and install kit, shouldn't there be power at the connection under the horn button as well?
 
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Old 12-04-2011, 08:26 PM
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The horn relay is looking for a ground. When you press the horn button, you are providing that ground. Since you have determined that the relay and horn are both good, something must be missing in the circuit from the relay back to the horn button and on back to the neg batt post. I'd check to see if there's continuity from the metal part of the steering wheel and the steering shaft to ground. The shaft/steering wheel must be common to the negative battery post - if they are isolated, the circuit won't work. You mentioned the rag joint. I think there's supposed to be a jumper across the rag joint for ground continuity. (My '75 has no rag joint) An easy way to check for continuity would be with a hot test light. If you touch the probe to the metal part of the steering wheel, the light will prove if it's grounded or not.

On the high beam indicator - I had to clean up and re-glue the foil where the connector plugs into the inst cluster on my '75. That also fixed my instrument lights and some guage problems too.

Good luck
 
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Old 12-05-2011, 06:54 AM
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Thanks paul, I did just that, ran a hot test light and the bottom of the steering shaft is grounded, but the top is not, so when i replace the rag joint i will also fix the ground issue......

now onto the high beam indicator light.... and see what that issue is.....
 

Last edited by chesire17201; 12-05-2011 at 06:55 AM. Reason: i cant spell
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Old 01-06-2012, 05:48 PM
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well, now I have a NEW issue with the horn, as in it won't STOP.....

After replacing the steering gear and rag joint with a jumper on the rag joint, found that the blue/yellow wire from the harness to the horn relay had no continuity, so I ran a new wire, now the horn works great, too great since it won't stop blowing.....regardless of whether the horn button is being pressed or not, or even it the wire to the steering wheel adapter kit is connected,and when wire to the horn is disconnected and you touch the neg batt cable to the batt, you can hear the relay trigger, so it doesnt seem to be a stuck relay.

I'm sure this is caveman simple, but it is just eluding me.

Any ideas?
 
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Old 01-06-2012, 05:58 PM
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Since the relay is working, the problem must be in the blue/yellow wire or the horn button. Seeing that you say it still blows with the horn switch disconected that reduces the problem to the blue/yellow wire itself.
Disconect the wiring harness plug that goes to the turn signal switch then hook the battery back up. If the horn doesn't blow then the problem is the blue/yellow wire in the column is grounded somewhere.
If the horn still blows then the problem is the blue/yellow wire is grounding somewhere between the relay and the turn signal wiring harness plug.
 
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Old 01-06-2012, 06:08 PM
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yes, it blows with the wire at the horn button disconnected, mind you this is with a grant steering wheel and adapter kit, not sure that matters or not.

as for the wire, thats brand new and new turnsignal/horn switch,....
when I use the test light as a hot test light and check the wire itself where it plugs into the relay it is grounded.
 
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Old 01-06-2012, 06:20 PM
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Somewhere between the horn relay and the horn button the blue/yellow wire is grounded. That's the only thing that will cause what's happening.
Unplug the turn signal harness at the column. If it doesn't blow the problem is in the column. If it still blows, the problem is before the column.
Even though the wire is new, go back and double check it's entire length. It has to be pinched or something to make it ground out.
 
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Old 01-07-2012, 05:15 PM
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Ok, I disconnected the harness and the horn did not blow when the neg batt cable was put on, so where does that leave me? Plug harness back in and it wailed like a banshee

One thing I did think of, the original turn signal switch only had one brass post contact (horn contact i assume?) my replacement switch has 2 of these, could that possibly be the issue?

Here are links to the contacts I am talking about on the signal switch.

http://desmond.imageshack.us/Himg607...jpg&res=medium

http://desmond.imageshack.us/Himg805...jpg&res=medium

also, thanks mike for the pic in this thread https://www.ford-trucks.com/forums/1...-question.html it helped me get my light working on the gear selector, i had wire wrong there, but the rest are spot on
 
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Old 01-07-2012, 05:24 PM
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If the turn signal switch has 1 brush, it's a ground-out style switch. This means the horn pad grounds the single brush to the steering shaft. This style grounds out the horn relay. If the turn signal switch has 2 brushes, it's a short style switch. This means the horn pad connects the two together. This is a newer style switch that closes the hot side of the horn. The two styles are not compatible.
 
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Old 01-07-2012, 05:28 PM
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ok, then i think thats the issue, the new one I put in has 2, so do I need to order a new one with only 1 and replace it again, or can I disconnect/remove something in this one?
 
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Old 01-07-2012, 05:35 PM
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I'm not familiar enough with your aftermarket steering wheel setup to answer that question; I can take a guess if you post a picture of the underside of the steering wheel. But at the end of the day you've got the incorrect later-model turn signal switch.
 


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