Having charging problem again
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Having charging problem again
This is a continuation from my last post"Don't have a clue".I thought i had my problem fixed.the truck starts now but it runs at a low idle,rough and wants to stall.The parts i replaced are as follows:battery(tested,found it was frozen).new alternator(got it tested,failed).new solinoid and positive battery cable.After changing all of that i started it,no high idle when cold,while idling the alt gauge would move back and forth then go to the low side does'nt move even when the engine is reved up and the battery light has come on.Is there a sensor involved in this problem,could the ECM or spark control modual be related?I looked at a wiring diagram in my repair manual and there is a green/red wire from the alternator that goes to the gauge in the dash,in this wire is a fuse link(as per manual)opened it and did not find a fuse.it looks like male/female connector.why would the gauge work then stop and the battery light come on?
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From: Easton,Ks
I looked at a wiring diagram in my repair manual and there is a green/red wire from the alternator that goes to the gauge in the dash,in this wire is a fuse link(as per manual)opened it and did not find a fuse.it looks like male/female connector.why would the gauge work then stop and the battery light come on?
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From: Virginia
I would first take a voltage reading at the battery with the truck running. It should be around 14v. If your idle is a little low, it may be around 13v but it should read higher than the reading with truck off.
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I did a test with a volt meter,with the truck not running i got 12.13 volts and when running i got 11.71 volts.Before doing this the new alternator i got it tested just to make sure it was not a lemon,it passed!could i have a broken wire going to one of the two connectors to the alternator?
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From: Virginia
With the engine off, make sure you have 12v on the large output wire or wires leaving the alternator. If you don't the fusible link is burned out in that wire.
You should also have a green/red wire going to the alternator. It should have power with the key in run, and no power with the key off. Also make sure the plug is not melted where the smaller wires plug in.
If all that checks out, I would take the alternator back to the store to be checked again. You will not be the first person to have trouble with a new alternator.
You should also have a green/red wire going to the alternator. It should have power with the key in run, and no power with the key off. Also make sure the plug is not melted where the smaller wires plug in.
If all that checks out, I would take the alternator back to the store to be checked again. You will not be the first person to have trouble with a new alternator.
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From: Virginia
Here's a diagram.
You checked the black/orange wires and they had battery voltage, so that fusible link is good.
You checked the lightgreen/red with the key on and off and thats working.
Make sure you have battery voltage on the yellow/white wire with the truck off.
Make sure the white/black jumper is in place.
You also may have the alternator that is famous for melting the plug that plugs into the alternator. Make sure it looks ok, I think you can buy replacement plugs with pigtails made onto them to splice the wires.
You checked the black/orange wires and they had battery voltage, so that fusible link is good.
You checked the lightgreen/red with the key on and off and thats working.
Make sure you have battery voltage on the yellow/white wire with the truck off.
Make sure the white/black jumper is in place.
You also may have the alternator that is famous for melting the plug that plugs into the alternator. Make sure it looks ok, I think you can buy replacement plugs with pigtails made onto them to splice the wires.
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From: Easton,Ks
Check the resistance from the frame of the alternator to the NEG post of the battery and if it is less than 5 ohms replace the alternator.
If it is more than 5 ohms clean your ground cable from th NEG post of the battery to the engine block.
You do not just have the ground cable of the battery going to the frame do you?
If you do it is wrong and needs to be changed.
If it is more than 5 ohms clean your ground cable from th NEG post of the battery to the engine block.
You do not just have the ground cable of the battery going to the frame do you?
If you do it is wrong and needs to be changed.
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I checked the ohms and i got between 4 and 6 ohms,as for the ground wire it is grounded to the body.there is also two other wires that are grounded in that same spot those wires come out of a bundle that i think go back to the alternator.To change the location of the ground(s) what is the minimum gauge wire i should use.