1990 GMC K1500 with an intermittent charging problem
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No I don't know off hand which alternator I have. I take it the P L F * or P L I * will be stamped on the alternator by the clip? I'll have to take a look.
I know just enough to be dangerous when it comes to electrical problems. The 3w 35-100 ohm resistor is that something NAPA would have or Radio Shack etc.?
Thanks for all your help. I'm getting a far better understanding of how this is suppose to work.
Steve
I know just enough to be dangerous when it comes to electrical problems. The 3w 35-100 ohm resistor is that something NAPA would have or Radio Shack etc.?
Thanks for all your help. I'm getting a far better understanding of how this is suppose to work.
Steve
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I just ran out and took a look and saw the P L F * stamped on the connector with the wire. So what would you suggest I do to run a new wire to the alternator and by pass the one from the instrument cluster? Thanks!!!
Steve
Steve
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there is also these, they have a 5w 85 ohm resistor already in the pigtail for simplicity
http://www.painlessperformance.com/w...rchField=30707
http://www.painlessperformance.com/w...rchField=30707
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Hey JWFirebird, thanks a million for the tip and the link. I'm going to order one of those pig tails and see what happens!
Thanks again!!
Steve
Thanks again!!
Steve
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Hey JWFirebird, with your advice I got my truck charging properly again. I got the pig tail you recommended from Painless. I wasn't sure if the in dash volt meter would work after I ran a different wire to the pig tail, so I put in an under dash volt meter as well.
I drove the truck about 30 miles today and both volt meters showed a charge, but what was odd is the idiot light would flicker on and off, stay on a bit then go out, but the whole time the volt meters showed a charge and I could tell it was charging cause I had to have the heater fan on the whole time and it never slowed down, so there wasn't any power loss, just a stupid idiot light. My guess is there is something haywire with the idiot light circuitry and that is what was causing all my problems.
Thanks again for you advice!!!
Steve
I drove the truck about 30 miles today and both volt meters showed a charge, but what was odd is the idiot light would flicker on and off, stay on a bit then go out, but the whole time the volt meters showed a charge and I could tell it was charging cause I had to have the heater fan on the whole time and it never slowed down, so there wasn't any power loss, just a stupid idiot light. My guess is there is something haywire with the idiot light circuitry and that is what was causing all my problems.
Thanks again for you advice!!!
Steve
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good to hear, that light was likely your problem before intermittent continuity through that circuit. you could just take the bulb out or whatever now.
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Hey JWFirebird, I think you are probably right it could be the light. I did replace the bulb when I had the cluster out, but maybe it'* the bulb socket as well.
I think when it warms up I'll take the cluster out again and give it a better inspection. The resistance that you mentioned in the excite wire, is it in the wire, the circuit board, or does the idiot light itself act as the resistor? Do you know what would happen if the idiot light were to burn out? Would that cause the thing to discharge. Man that would be a hassle, like the ole Christmas lites, one goes out they all do.
Thanks again for your advice. I had talked to a lot of folks, but you gave the best info!!
Steve
I think when it warms up I'll take the cluster out again and give it a better inspection. The resistance that you mentioned in the excite wire, is it in the wire, the circuit board, or does the idiot light itself act as the resistor? Do you know what would happen if the idiot light were to burn out? Would that cause the thing to discharge. Man that would be a hassle, like the ole Christmas lites, one goes out they all do.
Thanks again for your advice. I had talked to a lot of folks, but you gave the best info!!
Steve
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the resistance is the is the combination of the connectors, socket, and bulb. if your bulb burns out now it wont do anything because you have the alt bypassed with the pigtail. thats why you could just remove it if you wanted.
before you bypassed it the bulb goes out or like yours the connection starts going and you get no charge from your alt, its a pretty stupid design if you ask me. probably why they have a ready made pigtail to bypass it.
before you bypassed it the bulb goes out or like yours the connection starts going and you get no charge from your alt, its a pretty stupid design if you ask me. probably why they have a ready made pigtail to bypass it.
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Yea that is a stupid design. When you pull the cluster, the metal cover says something to the effect, do not take this cover off, because of the danger of static electricity. So they put the scare in you, you don't want to even replace dash bulbs. I figured, heck it ain't working so what do I have to loose.
Thanks again for the info!!!
Steve
Thanks again for the info!!!
Steve
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