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Old 03-14-2019, 06:11 PM   #26
Coalkracker
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Re: Help with dash lights

The switch is holding position. If i slowly pull down the handle the left blinker indicator turns on until it clicks and holds then the indicator lamp turns off but the outside lamps still blink.
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Old 03-14-2019, 06:14 PM   #27
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Re: Help with dash lights

So the headlights....ive been looking at some diagrams and i did a quick test with my meter. I am not getting continuity from the headlight plug at the headlight to the wire at the on/off switch. It appears that the wire runs through the foot switch but i havent tested at that point yet. Maybe im thinking the wrong way and you can correct me or is that where i should look next?
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Old 03-14-2019, 06:16 PM   #28
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Re: Help with dash lights

Btw i tested from driver side headlight plug tan wire to headlight switch blue wire i think.
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Old 03-14-2019, 06:20 PM   #29
Rick Bollinger
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Re: Help with dash lights

Also check from headlight plug high and low beams to a direct ground {battery} post to eliminate a bad ground.
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Old 03-14-2019, 06:33 PM   #30
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Re: Help with dash lights

Ok i just those two and nothing on both. I will check the foot switch next.
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Old 03-14-2019, 07:00 PM   #31
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Re: Help with dash lights

So i unplugged the foot switch and jumped the wires and my headlights turned on. The switch is pretty bad looking. Rust on the switch and the plug looks corroded also.
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Old 03-14-2019, 09:53 PM   #32
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Re: Help with dash lights

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Originally Posted by Coalkracker View Post
So i unplugged the foot switch and jumped the wires and my headlights turned on. The switch is pretty bad looking. Rust on the switch and the plug looks corroded also.
I'm helping a friend with his project truck that hasn't moved under it's own power in 10 years. We fix something and up pops a couple more problem areas.. Finally came to a quitting spot so I can follow up with you....

The correct term is "dimmer switch".. Let's use the correct terminology so others will know what component you're talking about.. Failure of the floor mounted dimmer switch is pretty common in old vehicles.. The switch is "trapped" under carpet, moisture seeps in and corrosion soon takes over.. Clean the plug terminals, replace the dimmer switch and you should have high and low beams working.. BTW, you're getting pretty good at electrical trouble shooting.. Just work on learning the correct terms for the components.. You'll find the correct terms on the wiring diagram...
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Old 03-14-2019, 10:29 PM   #33
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Re: Help with dash lights

I also got the turn signal switch to work correctly. I sprayed some de-oxit into it and worked it a bunch of times and it works perfectly now. I will order a new dimmer switch tomorrow and once thats all in order i have to troubleshoot my reverse lights.
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Old 03-14-2019, 10:33 PM   #34
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Re: Help with dash lights

First time seeing my cluster light up.
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Old 03-14-2019, 11:27 PM   #35
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Re: Help with dash lights

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First time seeing my cluster light up.
Nice.... You've earned a pat on the back...
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Old 03-14-2019, 11:32 PM   #36
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Re: Help with dash lights

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I also got the turn signal switch to work correctly. I sprayed some de-oxit into it and worked it a bunch of times and it works perfectly now. I will order a new dimmer switch tomorrow and once thats all in order i have to troubleshoot my reverse lights.
That's good to hear.. I was worried the turn signal switch might have been a mechanical failure -- broken plastic pieces... Does the horn work properly?? It shares some components with the turn signal switch..
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Old 03-14-2019, 11:35 PM   #37
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Re: Help with dash lights

It doesnt. I havent really done anything besides try it once or twice. Hopefully it will soon though.
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Old 03-15-2019, 01:03 AM   #38
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Re: Help with dash lights

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It doesnt. I havent really done anything besides try it once or twice. Hopefully it will soon though.
OK... The horn circuit works a bit different from light circuits.. The horn has a relay that is mounted to the inside firewall, above and slightly to the right of the fuse box..

Here's how the circuit works.. Battery voltage from the fuse box is fed to the normally open contact on the horn relay.. From the other contact terminal on the relay, a wire is routed to the horns. An "internal jumper" is routed from the battery fed terminal to one end of the relay coil winding.. A 3rd wire is routed from the other coil terminal into the turn signal column harness and terminated at a brush attached to the turn signal switch.. This wire is grounded when the horn button is depressed. The relay coil is energized, closing the relay contacts, which feeds the battery voltage to the horns.. When you depress the horn button, can you hear (or feel) the relay click?

Remember the basics.. Check for battery fed voltage at the relay.. Check the horn grounds where they mount on the core support. The "final ground point" is in the steering wheel under the horn button.. Remove the horn button and clean and polish the cupped disk and the inside surface of the steering wheel hub.. Check the fuse.. If the relay clicks when the horn button is depressed, check for voltage at the horns while the button is depressed..

This is a simplified version of how the horn circuit works.. There's more to it than these few words, but it's enough to get you started on the horn problem..
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Old 03-15-2019, 08:53 AM   #39
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Re: Help with dash lights

Ok great, check the horn off the list...works now!
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Old 03-15-2019, 08:57 AM   #40
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Re: Help with dash lights

I really appreciate all this help. This site has been better then any tool in my tool box so far.
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Old 03-15-2019, 05:55 PM   #41
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Re: Help with dash lights

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I really appreciate all this help. This site has been better then any tool in my tool box so far.
I'm 75 years old.. Started working professionally as an auto tech in early 1966 right after I got out of the military.. I spent over 30 years, earned numerous certifications along the way, working on vehicles from 5 decades.. I cut my eye teeth on vehicles of the '60s and '70s.. Not to sound like bragging, but there's not much I can't fix on these old trucks we love so much.. I'm glad I could help you get yours going... You listen and pay attention very well. I enjoy helping you..
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Old 03-15-2019, 06:21 PM   #42
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Re: Help with dash lights

Thank you! Maybe some help with the dimmer switch then? I stripped the darn screw heads so i tried drilling to use an ez out. Well now i have a snapped off drill bit in the screw. What should i try next?
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Old 03-15-2019, 07:14 PM   #43
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Re: Help with dash lights

Btw you have spent more years working on these vehicles then ive been alive so it wouldnt make sense for me to not listen. I could pay someone to do all this but i dont want to. I want to learn about these trucks because i plan on getting another one after this one is on the road. Im going to actually use this as a truck so im not going wild with making it really nice looking just everything functioning. My fathers friend bought this truck new when he came home from vietnam and had it until 2 years ago when i finally asked if i can buy it from him. It was just sitting next to his barn for years. Its not in the best shape but i like it. I wont have to worry about getting it dirty or messing up the paint when im using it for its intended purpose.
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Old 03-15-2019, 08:35 PM   #44
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Re: Help with dash lights

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Thank you! Maybe some help with the dimmer switch then? I stripped the darn screw heads so i tried drilling to use an ez out. Well now i have a snapped off drill bit in the screw. What should i try next?
An ez out might work, but there's an easier way.. The reason the drill bit broke was because you used one that's probably too small.. Do your best to remove the drill bit.. Using a 5/16" bit, continue drilling the screw just enough until you cut through the screw heads... Once the heads are gone, you can remove the dimmer switch.. Situate the harness totally out of your way.. You should now have a bit of the screws sticking up through the floor board.. Soak, and I mean SOAK, those screws with a good quality penetrating oil.. I use Liquid Wrench.. Might take a couple hours for the oil to soak into the threads.. Using vice grip pliers, grip the protruding part of the screw and work the vice grips back and forth.. Use finesse and patience. Those screws will turn loose and you won't damage anything in the process..
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Old 03-15-2019, 09:08 PM   #45
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Re: Help with dash lights

Yes the bit i used was small. I was trying to avoid hitting the threads. I hit it with some kroil and let it sit then used a phillips bit in a rachet so i could press as hard as i could while turning. But wow those things are really in there. I will give your way a go tomorrow. It sure is nice seeing all of the lights working on my truck so far. I am getting a pretty bad battery drain from someplace though. Im hoping i find it as i go through everything one by one.
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Old 03-16-2019, 01:17 AM   #46
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Re: Help with dash lights

My daughter and son-in-law showed up a few hours ago for a weekend visit.. We don't get to see them very often as my son-in-law has a season related "high demand" job and can't get away very often... I'll be visiting with them and probably won't be on the forum very much..

About that current drain.. Unless a bunch of modern electronic devices have been added to your truck, there's not many areas that cause a current drain if something fails.. Dome lights staying on due to a misadjusted door switch or headlight switch left in the "dome light on" position, glove box light (if equipped), and misadjusted and/or shorted brake light switch come to mind.. In these simple trucks, shorted mechanical voltage regulator and shorted alternator diodes are the most common source of battery drains.. Take a look at those items first.. I'll check in on your progress periodically.. If you don't locate the source of the drain, there is a method for tracking it down.. I'll go over it with you later as time permits..
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Old 03-17-2019, 03:55 PM   #47
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Re: Help with dash lights

I'm having no luck with these dimmer switch screws at all. I had the right one snap flush with the floor and I cant even get my vise grips to hold on the remaining stud anymore. I dont even think drilling the left one is an option, its too close to the side of the truck to get a straight shot at it with my drill. Id really like to get these out and use the original holes. I'm thinking about trying to pound a box wrench onto the stud but idk if thats going to mess it up more or help me.
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Old 03-17-2019, 04:52 PM   #48
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Re: Help with dash lights

Well I ended up getting fed up with it and drilled and tapped and used stainless hardware. So thats done. On to the battery drain. Everything under the dash is looking pretty good but dont want to rule anything out just yet.
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Old 03-17-2019, 05:26 PM   #49
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Re: Help with dash lights

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Well I ended up getting fed up with it and drilled and tapped and used stainless hardware. So thats done. On to the battery drain. Everything under the dash is looking pretty good but dont want to rule anything out just yet.
I can't say I agree with that technique in the least.. As a last resort I'd have removed the inner fender panel.. Using a small welding tip on my torch, I apply some heat to the screws where they protrude through the floor.. Let it cool and then spray some more Liquid Wrench to the screws from the top.. A little GENTLE twisting with the vice grips --- No pounding!!! -- Patience and finesse, with no "getting fed up".. But what is done is done..

Now, on to the battery drain... Before you get "fed up" again and set fire to the wiring harness --- Explain to me in detail how you diagnosed the problem as being a battery drain???
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Old 03-17-2019, 05:57 PM   #50
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Re: Help with dash lights

If i leave the battery connected its dead within a few hours. If i disconnect it, its good for months. I unplugged the F and R plug at the alternator and it did not make a difference. Ive only visually inspected the wires under the dash to see if anything looks bad. Thats as far as ive gone so far. No testing yet.
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