Wiring problems after a fire

[michwalt15]

Thanks franklin2. None of the loose wires have any power with the key on. I checked all the fuses and they're good.

 

[franklin2]

The grey red is power from the PCM. I am guessing it's the 5v supply. If there is no power there, check the power to the PCM itself. It has a relay and some red wires feeding it 12v. Here's a diagram on that.

 

[1mouse3]

These the other 4 wires I have coming off that harness, besides the ones for the lights on the passenger side. The ac is a green with a dark color sripe and a black with a yellow strip...

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I think this black with a yellow going back to the harness by the blower motor is the same one off the a/c, sorry did not do a resistance check to confirm this...

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The other is a red with a blue stripe, that is the remote wire for the starter.

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[michwalt15]

Thanks for the replies. Is there a one-wire alternator solution for these trucks? I know with my 68 camaro there was one.

 

[IDIBRONCO]

You can convert to a 3G, but that's more than one wire. I'm pretty sure that you can convert to a GM one wire alternator, but I'm not sure how to wire it in.

 

[1mouse3]

You can convert to a 3G, but that's more than one wire. I'm pretty sure that you can convert to a GM one wire alternator, but I'm not sure how to wire it in.

@michwalt15 has a 93, so is 3g with serpentine..

Thanks for the replies. Is there a one-wire alternator solution for these trucks? I know with my 68 camaro there was one.

The 3 wire plug on the 3g is simple to wire to its self...

I terminal - that need to go to a resistor or a bulb to ignition.
A pig tail for a turn light works well on my f100 wired to the ignition wire to the 6a box, you can tap into the one for the IP pump and zip tie the bulb where it wont get damaged.
S terminal - that gose to another plug on the alternator
A terminal - that gose to a positive sorce.
Just run this one to the positive post.

 

[IDIBRONCO]

@michwalt15 has a 93, so is 3g with serpentine..

Whoops. I forgot. I guess that comes with getting old.

 

[michwalt15]

@michwalt15 has a 93, so is 3g with serpentine..





The 3 wire plug on the 3g is simple to wire to its self...

I terminal - that need to go to a resistor or a bulb to ignition.
A pig tail for a turn light works well on my f100 wired to the ignition wire to the 6a box, you can tap into the one for the IP pump and zip tie the bulb where it wont get damaged.
S terminal - that gose to another plug on the alternator
A terminal - that gose to a positive sorce.
Just run this one to the positive post.

I spliced the I terminal through a tail light bulb and 12v.
The S terminal is as it should be.
I connected the A terminal to the battery.
The alternator is still not charging.
What should I do next?

 

[1mouse3]

I spliced the I terminal through a tail light bulb and 12v.
The S terminal is as it should be.
I connected the A terminal to the battery.
The alternator is still not charging.
What should I do next?

That sounds like a faulty alternator, because you gave it all it needs to work. Dose the bulb light up with the ignition on but engine not running? That is what it should do, if its always on the regulator in the alternator is bad and if it dose not light at all test the light to ground instead of the altenator before condemning the alternator.

 

[michwalt15]

It's always on. I'll go get the alternator checked.

 

[michwalt15]

It passed.

 

[1mouse3]

It passed.

You should check the resiance or the S terminal jumper wire to make sure its not bad, with both ends unpluged.

 

[1mouse3]

This guy dose a good job explaing the operation of the 3g alternator. If the tight you have works, that means the I teminal is good, You say the A terminal is hooked to the battery, you can check the wire with a test light to make shore its good. That leaves the S terminal jumper, as whats left that would keep the alternator from giving a output. I bockmarked this video where it show a diagram alternator, that shows that S jumper connecting the stater and the regulator together.

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[michwalt15]

Thanks for the video. The y/w wire was connected to ground. It's charging now but I've got 17.4v. What could be causing the high voltage? Batteries are already charged fully.

 

[1mouse3]

Thanks for the video. The y/w wire was connected to ground. It's charging now but I've got 17.4v. What could be causing the high voltage? Batteries are already charged fully.

This would be the regulator seeing low voltage or fault with the regulator, dont run the eninge till this is sorted since will cook the batterys. What do you get from these checks?


- Check voltage with the ground lead on the case of the alternator and positive test lead on the positive of the battery.
- Check voltage with the ground lead on the case of the alternator and positive test lead on the positive of the alternator.
- Check voltage with the ground lead on the case of the alternator and positive test lead on the y/w wire pin of the alternator pigtail unpluged, also have a grounded test light hooked up to the y/w wire pin at the same time testing to give load on this lead.
- Check voltage with the ground lead on the ground post of the battery and positive test lead on the positive of the alternator.
- Check voltage with the ground lead on the ground post of the battery and positive test lead on the positive of the battery.