92 dash stuff

Selahdoor

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Coming home on sunday, I saw a small curl of smoke creep up from my dashboard. Not a lot of smoke. Just a bit. And only barely detectable as electric in nature.

Today, I removed the dash, to see if I could find the culprit that released the magic smoke. Don't want to end up stranded on the road...

The smoke curled up out of the dash in this area...

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When I flip the dash over, the only thing that I can see that even remotely looks like it could be the culprit is this little resistor here:

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And it only barely looks burned.

Does anyone know what this resistor is for?
 

IDIBRONCO

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I can't answer what it's for, but the solder on each end looks like it's been pretty hot. I'll bet that you found the culprit.
 

Selahdoor

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Brand new headlight switch. No idea what GP would have to do with this.

~~~~~~~

I'm betting this is the oil pressure signal.

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If you look at any of the others, there is a 'sig' and a 'gnd'. I'd assume that is for signal and ground.

I have pointed those out for the volt meter on the left.

Now on this one, one end of that resistor goes to 'sig' for the oil gauge, and the other end of the resistor goes to the tab for the wiring harness.

While the third tag for the oil gauge goes to the ignition.

Again, I am betting this goes out to the oil pressure sensor.

Now to figure out WHY it would burn up the resistor...
 

Selahdoor

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Ah.

When I read GP on here, I think of Glow Plugs. LOL
 

Selahdoor

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Also, one of the first things I did to this truck was the headlight switch.

It was burned up.

I learned that it was such a common problem, that even Home Depot carries the headlight switch and connector!

I replaced the switch. Along with it's connector. And then built up a complete wiring harness for the headlights, using relays, and powering the headlights through the relays. Now the switch only has to switch the relays.
 

Jesus Freak

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I thought about GP meaning glow plugs as I was typing it, but I figured context would make it make sense. I still need to do my headlight stuff, but I really don't drive at night so I rarely think about it. And I'm electronically illiterate, thus I drive a mechanically injected diesel. Good luck and have fun with your resistor, don't forget to "giggle test" it.
 

Selahdoor

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Still have to figure out why the resistor would burn up.

Looking at the 3 lugs there... I am going to assume that the connection that goes through the resistor goes out to the oil sender unit.

Next assumption is that the oil sender unit is a simple resistive ground. More/less pressure = more/less ground, and that is how it 'sends a signal'.

With the ground lug being ground. Period.

And the ign signal lug, is where the power comes from for all this.

That is the way that it makes the most sense to me. But I can't figure out what would happen with the oil sender unit, to cause the resistor to burn.

Especially since the oil gauge continues to work normal!!!
 

Selahdoor

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So.

I have learned a couple things. Well, kind of already knew, just didn't know the details.

Already knew this oil pressure gauge was more or less just an idiot light. Just didn't know how it was set up and worked.

Here's the data. The 'sender' unit... It just an idiot light unit. If there is as little as 4 pounds of pressure, the idiot light is satisfied.

But when hooked to an actual gauge, the gauge shows always terribly low. To fix that, they put this resistor in. Now, if there is as little as 4 pounds of pressure, the gauge reads right in the middle.

To fix this, you have to put in the actual sender unit meant for a gauge. I still haven't found the part number for that.

Then jumper the connection you see above, right by the end of that resistor, to bypass the resistor.

Now your gauge should actually read like a gauge.


So... I need to find out what the part number is, for the actual gauge sender unit. (If you call the auto parts store, they are just going to sell you the sender unit for the idiot light.)
 

IDIBRONCO

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I still need to do my headlight stuff, but I really don't drive at night so I rarely think about it. And I'm electronically illiterate, thus I drive a mechanically injected diesel.
I kind of cheated and bought the headlight relay kit from LMC Truck. I put one in both the Red Truck and the Blue Truck. It was super simple. IIRC, the kits didn't include "instructions" and it was easy to figure it out. To be honest, the wires were all labeled as to where they go so instructions aren't really needed. I'll bet that the kits from Bronco Graveyard are the similar or the same.
 

Selahdoor

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I did my own because I don't like the wires they use in these 'kits'. I used wires that are at least 2 to 4 gauges larger than the ones they use. Plus I am certain of all my connections.
 

IDIBRONCO

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I did my own because I don't like the wires they use in these 'kits'. I used wires that are at least 2 to 4 gauges larger than the ones they use. Plus I am certain of all my connections.
I was just throwing out an option to one electrical dummy from another electrical dummy. Also, after having made several all night drives with the LMC kit, I haven't had one issue. I think it will be ok for quite some time.
 

Jesus Freak

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I was just throwing out an option to one electrical dummy from another electrical dummy. Also, after having made several all night drives with the LMC kit, I haven't had one issue. I think it will be ok for quite some time.
Hi I'm Jesus Freak and I'm an "electrical dummy"( muffled sounds of "hi Jesus Freak"). Yeah I've read books, watched video, talked to people, and messed with electricity but it just doesn't click with me. I'm certain that at some point I will meet the right person to explain it the right way and it'll make sense. But until then, the harness you discribed sounds like the ticket.
 
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