Bad charging/ headlight blowing problem

[cordes]

I noticed today that my voltage in the omni would climb to the very upper limit of normal and stay there for a while. I also noticed what I thought to be my PS pump belt squeeling like crazy. I cut off the PS belt tonight and went for a drive. All was well until my volts got really high again while I was giving it a decent dose of throttle. My headlights got very bright very quickly, and then all was black. The squeeling came back in a big way. I was able to drive it home with the volt gauge at about 17. The turn signals still work as does everything but the headlights, so I am thankful for that.

I had checked the acessory drive belt before taking off, and it seems fine.

What should I check first? I knew I got this car going to easily this year. :(

[BadAssPerformance]

Alternator? or Power Module?

My Dakota randomly does the high voltage thing too... The alternator on it is somewhat new so I need to swap the stock SBEC in and see if that fixes it.

[cordes]

Alternator? or Power Module?

My Dakota randomly does the high voltage thing too... The alternator on it is somewhat new so I need to swap the stock SBEC in and see if that fixes it.

That is the way I was leaning. I am kind of thinking it might be the alt since the belt is making the "funny squeekey noises". It is a new alt from advance auto, or perhaps it was rebuilt, but either way it is only about a year old. How would I go about checking those things? My electrical abilities are weak.

[BadAssPerformance]

Advance or most parts stores can test the alternator.

the old 'disconnect the battery while it is running to see if the alternator keeps it running' test wouldnt work for this issue...

my guess is the PM if the alt is newer and the voltage is bouncing up since voltage regulation is in the PM.

[cordes]

Advance or most parts stores can test the alternator.

the old 'disconnect the battery while it is running to see if the alternator keeps it running' test wouldnt work for this issue...

my guess is the PM if the alt is newer and the voltage is bouncing up since voltage regulation is in the PM.

Oh, lordy now I need to test more things, and buy more stuff. Will it ever end???

Any advise on where to start for the headlights? I would imagine that I will test for voltage at the plug but then what?

[BadAssPerformance]

If your voltage is spiking like you say, that will make your headlinghts get bright and possibly pop... fix that and you might get a 2-fer.

Spend more money? is the alternator under warranty? Also, if you dont have a spare PM, just swap the one in from the 600 :thumb:

[cordes]

If your voltage is spiking like you say, that will make your headlinghts get bright and possibly pop... fix that and you might get a 2-fer.

Spend more money? is the alternator under warranty? Also, if you dont have a spare PM, just swap the one in from the 600 :thumb:

I thought of that right after I posted. I think the alt. is under warranty, but we shall see.

Oh, and the headlights definitely popped. I could see forever for a brief second before they went out. It was actually kind of cool until I was out in the country with only my flashers to illuminate the way.

[BadAssPerformance]

LOL... "wow is that Indiana on the horizon?" *POP* "where did Illinois go?" ;)

[turbovanman²]

Its not the alternator. When it overcharges, it means the alt is working but no regulation, so a PM is in your cards.

Yep, you blew your headlights, and the squealing belt was due to the mega load the full fielded alt was putting on the belt, trust me, it was alot.

[BoostedNihilist]

the voltage regulator is part of the power module?

[cordes]

the voltage regulator is part of the power module?


Yes, it is in the PM.

Thanks Simon, I will swap it out with a know good one from my 600.

JT, it seriously was about like that.

[BadAssPerformance]

LOL.. you need some street lights out in the boonies ;)

[cordes]

LOL.. you need some street lights out in the boonies ;)

Whoa now, we have MULTIPLE stop lights in my town thank you. We can't even count the streetlights. This is the big city. pop. 4,500 :thumb:

[BadAssPerformance]

two words... bustling metropolis :thumb: :D

[MiniMopar]

My vote is that either the alternator field is getting shorted (internally or via a wiring issue) or the LM's ground is floating up, messing with the reference voltage (looks like a voltage sag to the LM when the ground floats). The regulator is in the PM, but it is controlled by the LM.

[cordes]

My vote is that either the alternator field is getting shorted (internally or via a wiring issue) or the LM's ground is floating up, messing with the reference voltage (looks like a voltage sag to the LM when the ground floats). The regulator is in the PM, but it is controlled by the LM.


Russ, what do you mean when you say that the LM's ground is floating up?

[turbovanman²]

Oops, my bad, you can still have a bad alternator. I just had an overcharging issue with my customers 86 GLHT and it turned out to be the alt, and the damn thing was rebuilt, or supposed to be but looking inside, its a crap job.

I installed a Nippo also, piece of cake.

[cordes]

Oops, my bad, you can still have a bad alternator. I just had an overcharging issue with my customers 86 GLHT and it turned out to be the alt, and the damn thing was rebuilt, or supposed to be but looking inside, its a crap job.

I installed a Nippo also, piece of cake.

Thanks. That is good to know. I think that this might have been a rebuild nippo unit, but I can't recall. I will try to swap power modules first and go from there. I will let everyone know what it was when I get to the bottom of it.

[TopDollar69]

What did you end up finding with this problem?

[cordes]

What did you end up finding with this problem?

It ended up being a very, very, small abrasion on one of the field terminal wires. I had to pull the whole sub-harness out to see it.