Hazards failed, subsequent instrament panel failure

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Newtron
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Hazards failed, subsequent instrament panel failure

Postby Newtron » Thu Feb 14, 2019 8:31 pm

So I pretty much suck at life, and electricity, so hopefully yall can help. 86 pup. Parked outside the other night at a friends had to leave the truck on the road with the hazards on. Got back into truck, turned hazards off. All of a sudden no blinkers working either. They came up on the instrument cluster solid that night. The next morning turned it on and still no working blinkers or lights turning on in the instrument cluster.

I checked the fuses. The 3rd fuse was blown (which was does do the hazard lights according to a shop manual) but the one labeled turn signals was fine. The blown fuse explained why I had no horn or overhead light in the cab. I replaced it got the horn back and the interior light, but no hazards and still no turn signals. I turned the hazards on and off multiple times and still nothing, but this time the #3 Fuse remained intact.

I fiddled around with the switch on the steering column and figured it could be in there, bad contacts and such. Took it apart, rebuilt and found voltage running thru that switch. I then tried a new flasher unit. I pulled the hazard tab. It clicked once, then stopped, blew fuse #3 again, and then simultaneously blew out all the lights, the tac, the fuel gauge and temp gauge on the instrument panel. I still have headlights, I still have a light that illuminates the instrument panel when the lights are on, I still have radio. Is there a instrument panel fuse or relay somewhere? or do I just have a mega short somewhere?

Where do I go from here. I'm feeling like my 86 pup is trying to mock my inability to understand electricity.
1982 2x4 Diesel Pup Two Tank WVO System
1981 2x4 Diesel Pup DLX Long Bed
1986 4x4 Turbo Diesel Pup Space Cab (roomate moved out with it, but still see it often)

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Halden
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Re: Hazards failed, subsequent instrament panel failure

Postby Halden » Sat Feb 16, 2019 11:18 am

I can draw up a quick diagram for you later today if you'd like. It sounds like you have a short somewhere. On both fuses 4 and 3. Fuse 4 feeds the panel
Halden
It's not pronounced "Ih-soo-zoo", it's pronounced "It-screws-you"
83 LS Long Bed Diesel 4x4
82 LUV Short Bed Diesel 5 Speed 2wd
64 Chevy C20 w/ 283 & 4 speed.
05 Sonata with a standard

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Halden
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Re: Hazards failed, subsequent instrament panel failure

Postby Halden » Sat Feb 16, 2019 6:37 pm

Don't know if this will help or not, but here is the schematic for the flashers and signals
Attachments
Turn Signal and Flasher.pdf
(104.96 KiB) Downloaded 60 times
It's not pronounced "Ih-soo-zoo", it's pronounced "It-screws-you"
83 LS Long Bed Diesel 4x4
82 LUV Short Bed Diesel 5 Speed 2wd
64 Chevy C20 w/ 283 & 4 speed.
05 Sonata with a standard

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puttputtinpup
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Re: Hazards failed, subsequent instrament panel failure

Postby puttputtinpup » Sat Feb 16, 2019 7:36 pm

I once had an 85 pup where the harness that came through the firewall and went under the dash had fallen down against the clutch and brake mechanism. The movement of the clutch pedal had worn the insulation off one of the wires causing a dead short. It would blow the main fuse as soon as I pushed the pedal in.

I'd suggest looking under the dash and inspect the harness and everywhere it may be rubbing on something and grounding out. Take the clamshell off the steering column and inspect the multiswitch harness for rubbing on metal parts.

One other thing I'd check on, weird I know, is the bulbs. Bad bulbs or sockets (and light socket ground points) can do weird things.

You changed the turn switch and didn't fix it... actually made it worse, so I'd start looking near there.

Donald NZ
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Re: Hazards failed, subsequent instrament panel failure

Postby Donald NZ » Mon Mar 11, 2019 1:07 am

When im trying to find tricky 'shorts' I substitute the fuse for a headlight bulb
yup a standard headlight bulb with two wire connected one to either side of fuse , watch out two wire strands dont touch from either side of fuse
this limits the power used to that which the bulb consumes so say around 5 amp

this way I can watch the bulb if its dim the problem is not there and if its bright it is.

so i'd turn the hazards on and watch the bulb, if bright Id disconnect the back half of the truck [ by the drivers kick panel is usually a handy connector ]

I'll keep disconnecting until the bulb goes dim , then I know I'm onto where the fault is.

saves feeding 2o fuses into the suspect fuse holder and destroying your flasher unit.

Newtron
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Re: Hazards failed, subsequent instrament panel failure

Postby Newtron » Mon Sep 02, 2019 6:24 pm

Ok still working on this problem. First I seem to only have 1 flasher unit in the 86 pup. I cant find another. Would this wildly effect that tidy wiring diagram Halden wrote? I figure not too much.

Also now I have sorted out some problems that were not talked about earlier. Some of the issues were from a loose harness from the alternator. This was causing the fuse for the horn and dome lite to blow I think. It started making a clicking sound at one of the relays by the fuel pedal, which happened once before when I had an alternator issue. So now all I'm trying to sort out is the blinkers and hazard lights.

The newest thing I have going on is that I have 12v constantly at the wire that is labeled ground (brown with white stripe) on the one wiring harness that plugs into the one flasher unit. This brown wire comes directly from the turn signal switch on the column. It has 12v as soon as I turn the key the key over 2 clicks, not even starting the truck. This wire is obviously getting power from some sort of short, but can it be getting power from a bad bulb connection if I'm not even asking for any signal lights to be working? It must be getting lots of power because it partly melted the old flasher and is instantly blowing a 20 amp fuse. is the move here to just chase this brown wire, or do all the bulb cleaning.

Thanks
1982 2x4 Diesel Pup Two Tank WVO System
1981 2x4 Diesel Pup DLX Long Bed
1986 4x4 Turbo Diesel Pup Space Cab (roomate moved out with it, but still see it often)

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Halden
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Re: Hazards failed, subsequent instrament panel failure

Postby Halden » Tue Sep 03, 2019 9:45 pm

Newtron

I looked at my 86 manual. It would appear the circuits are different. I'm not sure what year they changed. Earlier models apparently used two two wow flasher units. One for signals and one for hazards. I'd want to compare them side by side before I say how different they are.

To me it sounds almost like a melted wire or two since you mentioned things getting hot. Something similar happened to me years ago. What I do when looking for a short is stick my meter on ohms/continuity with everything unplugged stick a probe on the "ground" side of the fuse and the other probe to a ground plug things in starting as close to the problems circuit's fuse. Wait for your meter to show a change. I recently had to do this and found a bad crank sensor harness on one of my vehicles.
It's not pronounced "Ih-soo-zoo", it's pronounced "It-screws-you"
83 LS Long Bed Diesel 4x4
82 LUV Short Bed Diesel 5 Speed 2wd
64 Chevy C20 w/ 283 & 4 speed.
05 Sonata with a standard