Electrical trouble
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Electrical trouble
i have a 1993 ford f150 4x4. The altenator is charging but not charging the battery. The volts on the battery are 12.43 when the truck in not running and keeps dropping when the truck is running. I have checked all grounds. Need some help.
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From: Easton,Ks
Originally Posted by waynebutt
i have a 1993 ford f150 4x4. The altenator is charging but not charging the battery. The volts on the battery are 12.43 when the truck in not running and keeps dropping when the truck is running. I have checked all grounds. Need some help.
If it is charging than you have an open fuse link (or fuse) between the alternator and battery or a bad plug at the alternator.
Also check for a bad connection at the starter relay battery side with the battery cable.
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From: Sunny tourist infested FL
Sounds like the battery may have a dead cell....
12.43 sounds normal, but try this...
Check the voltage with the engine off. Start the engine then turn it off. Re-check the battery voltage. This wil take the "surface charge" off the battery.
If it's still 12.43, then the battery is good.
If your engine is running and the voltage is dropping, the alternator is bad. Or your have a major voltage draw somwhere in the system.
On the Alternator plug their is a black/orange. The wire leads a fuseable link. Check this fuse. It it's gone, no charge will reach the battery. I have a electrical diagram on CD, but no way to snap shot it so a can post it.
If I can find a way to take a snap shot of the page/pages, I'll post the diagram and troubleshooting procedures.
12.43 sounds normal, but try this...
Check the voltage with the engine off. Start the engine then turn it off. Re-check the battery voltage. This wil take the "surface charge" off the battery.
If it's still 12.43, then the battery is good.
If your engine is running and the voltage is dropping, the alternator is bad. Or your have a major voltage draw somwhere in the system.
On the Alternator plug their is a black/orange. The wire leads a fuseable link. Check this fuse. It it's gone, no charge will reach the battery. I have a electrical diagram on CD, but no way to snap shot it so a can post it.
If I can find a way to take a snap shot of the page/pages, I'll post the diagram and troubleshooting procedures.
Last edited by wildcard30; Mar 25, 2006 at 05:01 PM.
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From: Easton,Ks
You need to unplug the ISA plug from the alternator and see if you have battery power on the LG/R wire with key on.
If you have battery power there then you to find out if you have battery power at the Yellow wire with a white stripe (A wire).
You more than likely do not have power on one of these two wires, let us know the wire with no power and we will help you from there.
Also make sure you have Battery voltage at the B+ on the Alternator.
If you have battery power there then you to find out if you have battery power at the Yellow wire with a white stripe (A wire).
You more than likely do not have power on one of these two wires, let us know the wire with no power and we will help you from there.
Also make sure you have Battery voltage at the B+ on the Alternator.
Last edited by subford; Mar 25, 2006 at 04:57 PM.
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I am having the exact same problem with a 94 Explorer. There is NO voltage on the LG/R wire when the key is on.
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From: Easton,Ks
Originally Posted by PrescottRanger
I am having the exact same problem with a 94 Explorer. There is NO voltage on the LG/R wire when the key is on.
This could be at any of the plugs from the alternator to the Ignition switch or the wire itself could be broken open in the harness anywhere along the way.
This may help
Last edited by subford; Mar 25, 2006 at 08:34 PM.
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From: Easton,Ks
Originally Posted by PrescottRanger
Thank You Thank You -- While I haven't found the broken wire yet, I ran a jumper from the battery to the alternator and it started charging just fine. Could a burned out insterment panel bulb cause the open??
On the other hand I have heard of reports that said that they had a bulb burned out and when they replaced it, it started charging. I do not know what years they were talking about and if they had the resistor or not. Also if they had a resistor it may have been bad.
Last edited by subford; Mar 26, 2006 at 09:47 AM.
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voltage problem mostly in idle?
Hello I have a 94 f150 4x4 (5.0 302 efi). My problem is when im in idle and rev the gas pedal my voltage meter drops way down to just about make the truck stall in most cases it will stall. I have put a brand new alternator in the truck but have'nt done anything with the battery as of yet. When i drive the truck it doesnt happen to much but i know this isnt normal. I just bought the truck about a week ago and everything else is in perfect working order but this problem hmm... Any help would be greatly appreciated! Thank you,
Scott g
Scott g
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From: Easton,Ks
Originally Posted by waynebutt
I unpluged the ISA plug, there was no power on LG/R wire. There was power on yellow/white and power on orange and black
The Alternator also uses this wire to turn the Indicator light off.
If you do not have battery power on the wire with ISA plug unplugged and the key is turned on then you will have to trace back towards the Ignition Switch from the ISA Plug.
It could be a bad plug, open wire (broken) and some say the Indicator light bulb itself burned out can do this, but as I said above the 510-Ohm resister around the bulb is supposed to prevent this.
The diagram below will tell where the plugs and splice are located.
Good Luck.
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From: 3rd Rock
Originally Posted by scottyg
Hello I have a 94 f150 4x4 (5.0 302 efi). My problem is when im in idle and rev the gas pedal my voltage meter drops way down to just about make the truck stall in most cases it will stall. I have put a brand new alternator in the truck but have'nt done anything with the battery as of yet. When i drive the truck it doesnt happen to much but i know this isnt normal. I just bought the truck about a week ago and everything else is in perfect working order but this problem hmm... Any help would be greatly appreciated! Thank you,
Scott g
Scott g
…..See you on the boards.
