Not charging
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From: Toms River NJ
Not charging
I'm perplexed!
It's a 91 F150 302/AOD
The truck quit charging. I figure no big deal, been there done that.
The old alternator tested bad, so I put a rebuilt unit in, no good.
I took that one back and got another one from a different store. Had them test the new one and it's fine.
So I replaced all the alternator connectors. Still not charging.
I'm only reading battery voltage (12.5 now) and when I start the truck it drops 1/2 volt.
Any ideas?
Thanks,
Denny
It's a 91 F150 302/AOD
The truck quit charging. I figure no big deal, been there done that.
The old alternator tested bad, so I put a rebuilt unit in, no good.
I took that one back and got another one from a different store. Had them test the new one and it's fine.
So I replaced all the alternator connectors. Still not charging.
I'm only reading battery voltage (12.5 now) and when I start the truck it drops 1/2 volt.
Any ideas?
Thanks,
Denny
Fleet Owner
Joined: Aug 2005
Posts: 23,666
Likes: 301
From: Easton,Ks
More than likely you have an open fuse link at the Starter Relay. Check for battery voltage on the back of the alternator at the “B” terminal. If zero no charge and the fuse link is open.
The fuse link is OK check the Green wire with a red stripe at the back of your alternator "I" terminal. This wire needs to be about 1 volt below battery voltage to charge, if it is zero no charge.
The fuse link is OK check the Green wire with a red stripe at the back of your alternator "I" terminal. This wire needs to be about 1 volt below battery voltage to charge, if it is zero no charge.
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From: Toms River NJ
Thanks for the info and your time Bill.
I have battery voltage at both wires on the B terminals and 1 volt below battery voltage at the green wire with a red stripe.
I checked these through the plug ends with the volt meter ground on the battery.
Any other ideas?
I have battery voltage at both wires on the B terminals and 1 volt below battery voltage at the green wire with a red stripe.
I checked these through the plug ends with the volt meter ground on the battery.
Any other ideas?
Last edited by DennyB; Aug 10, 2007 at 05:35 PM.
Fleet Owner
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From: Easton,Ks
Might try it again with a test light to put a load on the circuit. Meters lie a lot in these circuits.
Never use a meter if a test light will do, it will save you a lot of time and money.
Also it sounds like you are saying you have a 2G Alternator. With these you almost always have to replace the plugs that plug into the alternator when you change out the alternator.
Never use a meter if a test light will do, it will save you a lot of time and money.
Also it sounds like you are saying you have a 2G Alternator. With these you almost always have to replace the plugs that plug into the alternator when you change out the alternator.
Last edited by subford; Aug 10, 2007 at 07:09 PM.
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From: Toms River NJ
Bill,
I didn't have a test light so I soldered one together real quick with a 12V bulb..
Guess what, no light at the B terminals. So fusible link must be the problem.
Now for the dumb question, where is it and how do I fix it?
Thanks again!
Denny
I didn't have a test light so I soldered one together real quick with a 12V bulb..
Guess what, no light at the B terminals. So fusible link must be the problem.
Now for the dumb question, where is it and how do I fix it?
Thanks again!
Denny
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Joined: Oct 2002
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From: Toms River NJ
Originally Posted by subford
.............................
Also it sounds like you are saying you have a 2G Alternator. With these you almost always have to replace the plugs that plug into the alternator when you change out the alternator.
Also it sounds like you are saying you have a 2G Alternator. With these you almost always have to replace the plugs that plug into the alternator when you change out the alternator.
I went ahead and replaced both plugs this time.
Fleet Owner
Joined: Aug 2005
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From: Easton,Ks
If you have loaded battery voltage at the two B's and voltage at the green/red and the alternator is grounded and turning it should charge, if not take it back.
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From: Toms River NJ
Perhaps I was not clear.
With the test light I have no light at the B terminals.
Where is the fusible link and how do I fix it?
With the test light I have no light at the B terminals.
Where is the fusible link and how do I fix it?
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From: Toms River NJ
Hey Bill,
I found the fusible link. it says use fuselink 14GA on it.
There is a real soft spot in the middle of it so that seems to be the issue.
Thank you very much for your time!
Denny
I found the fusible link. it says use fuselink 14GA on it.
There is a real soft spot in the middle of it so that seems to be the issue.
Thank you very much for your time!
Denny
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