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Old 10-04-2003, 11:14 PM   #1
Hoosierdaddy
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electrical problems-- has anybody ran into this??

I have a 71 I'm trying to get rolling. I finally got the big block purring smooooooth. Now I'm working on other little details like tail lights and replacing steering wheel and fixing things like sticky windows. Problem one: I was working on sticky windows and sprayed some Tri-flow on rails and pivit points. Now the window drops about 2 inches as soon as you close the door. problem 2: trying to fix tail lights... I checked for power at fuse box good on both sides of the fuse.. checked half way back under truck, power there too... got back to the plug and no power. went back to half way and nothing. checked wires as the come through dash, nothing.. went to switch and had power in but nothing else. turned lights on and off then I had power again. but tail lights still don't work. I replaced the switch with a new one... Now the dome light wont shut off, and the head lights appear to be on low beam but the light on the dash in indicating high beams. I got a couple burned out bulbs in the dash to replace, but that surely could'nt be the problem. Has anyone every ran into these problems? Also the left blinker flashes fast while the right flashes slower....



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Last edited by Hoosierdaddy; 10-04-2003 at 11:18 PM.
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Old 10-04-2003, 11:54 PM   #2
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The quick simple answer is bad grounds. That said, finding them can be a real headache. That is definitely what is causing the blinker problem, and likely the tail light problem. The tail lights are grounded through the bed to the frame. You might try a short ground strap under the bed to the frame.

Good luck
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Old 10-05-2003, 12:16 AM   #3
BLACK AND BLUE 67-72
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No, the blinker problem could be that a bulb is bad or not making good contact. I have seen this problem several times, where a bulb was bad and caused one side to blink faster than the other, or if the relay was bad both sides flash fast.
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Old 10-05-2003, 12:29 AM   #4
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Electrical problems suck. Bad grounds? Yup and had that problem many times before. When trying to figure out power to a source start from the fuse box with a test light and work your way through the circuit. If you are experiencing power and then nothing I suspect you have either a soft ground or an interuption (like a loose or broken wire) in the circuit somewhere. Put your test light on the wire you suspect and start moving the wires watching the test light to see if it goes on or off. Basic wiring trouble shooting is pretty straight forward if you take your time and don't get flustered. As far as your window problem it is possible that your window crank is worn badly and has to much slack in it. The lubrication just made it that much easier for the crank to fail. Also check that you don't have any broken pieces in your channels or spot welds that may have come loose.

Last edited by western star; 10-05-2003 at 12:33 AM.
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Old 10-05-2003, 12:30 AM   #5
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Also, with the problems after you got the new switch, it could be defective. A friend of mine went to O'Reilly's and got a new switch, well the Hi-Beams did not work so he took it back, then the dome light would not work, so he took that one back installed the new one and the dash lights did not work until you turned on the dome light! So he took that one back and got yet another new one, Guess what? No headlights!! Took that one back and got another one and only one side of his tailights would come on, Yep another bad switch!! So he said for the last time that he was taking it back, and he got this last switch and it was no good either, made one more trip and finally got one that worked!! So you can see that it's not always the ground. The bad part is the old switch worked fine until he went to take the dash out, and did not know about the little button on top of the switch! So he pulled really hard and wound up breaking the switch!!
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Old 10-05-2003, 12:58 AM   #6
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I have a head light switch that won't come out. You can push and play with that little button all you want and the switch handle or knob will not come out. Right now this is not a problem but when I get my brand new bazel it will be a problem. Of coarse I could always leave the switch in the old dash and buy another one for the new dash.
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Old 10-05-2003, 01:03 AM   #7
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Have you tried pulling the switch out and then pressing the button while pushing and pulling on the switch? Sometimes that has worked for me.
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Old 10-05-2003, 01:12 AM   #8
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Yes so many times that my finger started to bleed. I have removed switches like these for years and have never had one that had a mind all it's own. I'm pretty sure there is a gremlin in there that is holding it back.
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Old 10-05-2003, 12:12 PM   #9
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Yep, I had problems with the knob coming off also. I took the switch a part, as I thought it was no good anyway. I think there was not enough travel in the button to release the knob, because once a part, I depressed the lever inside the switch and the knob came out almost by itself. I'm almost sure the switch was bad because while I had a test light on the prongs of the plug at the back of the truck, my son slowly pulled the switch out and it would have power part way through the throw of the switch and then would drop off at the end of the throw. But thanks for the tips, I'll start with the grounds. That sounds like it could be the problem. I had a heck of a time getting a ground with the test light. But will no stone unturned. Thanks again for all the help. It's great to have all this expert help at the tip of my fingers. Well it's off to the garage, hope I can get something done today. Can't wait to take the old girl out on her first cruise since 1991.

Thanks again
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Old 10-05-2003, 01:16 PM   #10
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With the headlight switches being bad, new models look very much like old models...except the location of pins. O'rileys may have just been grabbing the ones that *looked* right.
As for the head light knob, if you can't get the shaft off, just grab the knob and pull like a mo-fo. The knob will come off leaving the shaft. Then you can remove the bezel. I have found that you can remove it like this about 5 or 6 times before it is too loose to stay on the shaft.
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Old 10-05-2003, 01:32 PM   #11
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Hook up the test light to the neg batt cable. (Disconnect cable first and the light is hooked up in line between cable and post). This turns the test light on. Then have your son start pulling fuses one by one till the light goes out. This way you narrow down which circuit to inspect.
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Old 10-05-2003, 10:27 PM   #12
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Blinkers flashing at different rates can be as simple as the flasher. I used to be in the auto repair field, and once spent hours trying to find an electrical problem for one side flashing, and the other not at all. Turned out to be the flasher!!!!!! Now it's the first thing I try when I have a signal problem. Oh, and don't buy the cheap short flasher...spend the extra money for the heavy duty trailering one...it will be worth it. Good Luck!
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Old 10-05-2003, 11:23 PM   #13
Longhorn Man
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Better yet, get an alectronic one. It'll blink the same rate regardless of load.
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Old 10-08-2003, 11:26 PM   #14
Denny
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I had the same problem with headlight switch knob not wanting to come out. I found that if you turn the flat side of the rectangular shaft to the top and pull out knob, then push on the button it comes out every time. Good luck hope this helps.
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