Alternator charge cable
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Senior User
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From: Oregon
OK - I never messed with that wire or that connector - is it tied into the factory charge cable in some way?
I guess what I am asking is if I need to splice a wire or something to get this to work. It obviously works with the factory cable and does not with the new one. That tells me that there is something else tied into that factory charge cable.
Or do I just need to leave the factory charge cable connected at the relay side but not the alternator side?
I guess what I am asking is if I need to splice a wire or something to get this to work. It obviously works with the factory cable and does not with the new one. That tells me that there is something else tied into that factory charge cable.
Or do I just need to leave the factory charge cable connected at the relay side but not the alternator side?
Fleet Owner
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From: Easton,Ks
Do not know what you mean by relay or alternator side. The the charge wire from the alternator only goes to the battery side of the starter relay.
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From: Oregon
Thank you again. I appreciate the help.
My original plan was to just tape up the ends of the factory charge cable itself so I do not have to hack into the factory harness at all, then just run a new charge cable from the alternator to the relay post or battery. Guess I have one more step to do.
My original plan was to just tape up the ends of the factory charge cable itself so I do not have to hack into the factory harness at all, then just run a new charge cable from the alternator to the relay post or battery. Guess I have one more step to do.
Fleet Owner
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From: Easton,Ks
Note that I used C123 as that is what was used for the connector in post number 9 in this thread.
In the Ford 1994 EVTM and the image below it is connector number 139.
Also if you just ran the large cable wire then you are also missing the wires that are pointed to in the diagram below.
/
In the Ford 1994 EVTM and the image below it is connector number 139.
Also if you just ran the large cable wire then you are also missing the wires that are pointed to in the diagram below.
/
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From: Oregon
Sorry I don't think I am being clear enough about what I did so here it goes:
What I did was use the factory harness plugs for the new alternator - the three prong plug that plugs into the connector labeled ASI, and the single skinny connector - they look to be C154 and C153, respectively, on that diagram. I disconnected the charge cable from the alternator post AND the starter relay post, taped up the ends with electrical tape, then laid a new charge cable from the alternator post directly to the positive battery terminal. This configuration did not turn on the alternator. When I disconnected the new charge cable from the alternator and battery terminal and re-connected the factory charge cable at the alternator and starter relay post, it did activate the alternator.
So which wire(s) do I need to splice into, and where does it need to run?
What I did was use the factory harness plugs for the new alternator - the three prong plug that plugs into the connector labeled ASI, and the single skinny connector - they look to be C154 and C153, respectively, on that diagram. I disconnected the charge cable from the alternator post AND the starter relay post, taped up the ends with electrical tape, then laid a new charge cable from the alternator post directly to the positive battery terminal. This configuration did not turn on the alternator. When I disconnected the new charge cable from the alternator and battery terminal and re-connected the factory charge cable at the alternator and starter relay post, it did activate the alternator.
So which wire(s) do I need to splice into, and where does it need to run?
Fleet Owner
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From: Easton,Ks
I think I know what you are saying and if so the "A" wire #36 Y/W has no power on it with your new wiring and no it will not charge.
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From: Oregon
Ok I think I am finally getting it...I appreciate your patience.
#36 is what turns the alternator on, and it is not receiving any power because it receives its power from the charge cable itself - if I read that diagram correctly it originates from a fuse link within the factory charge cable.
If I hooked up the factory charge cable back to the starter relay post, but left it disconnected and taped up at the alternator, would wire 36 still draw the power it needs to turn on the alternator with the new charge cable hooked up - or do I need to splice?
#36 is what turns the alternator on, and it is not receiving any power because it receives its power from the charge cable itself - if I read that diagram correctly it originates from a fuse link within the factory charge cable.
If I hooked up the factory charge cable back to the starter relay post, but left it disconnected and taped up at the alternator, would wire 36 still draw the power it needs to turn on the alternator with the new charge cable hooked up - or do I need to splice?
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From: Easton,Ks
Yes it would.
#36 is the power source for the alternator rotating field windings so the alternator can charge and must be on the battery side of the starter relay.
#904 turns the alternator on and off.
#36 is the power source for the alternator rotating field windings so the alternator can charge and must be on the battery side of the starter relay.
#904 turns the alternator on and off.
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From: Oregon
Excellent!
C139 (or C123 in your picture of the alternator harness above) is still connected so I am assuming that wire 904 will still be functional with my new setup, since it appears to draw its signal from the ignition switch, and is not tied into the factory charging cable.
Whew. I'll hook everything back up again and report back.
C139 (or C123 in your picture of the alternator harness above) is still connected so I am assuming that wire 904 will still be functional with my new setup, since it appears to draw its signal from the ignition switch, and is not tied into the factory charging cable.
Whew. I'll hook everything back up again and report back.
Fleet Owner
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From: Easton,Ks
Yes wire 904 it gets power from the ignition switch but it is also inside the factory charging cable (harness).
C139 is where wire 904 hooks to main harness from the factory charging cable (harness).
C139 is where wire 904 hooks to main harness from the factory charging cable (harness).
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From: Oregon
Got everything hooked up again leaving the factory charge cable connected at the starter relay but disconnected (and heavily taped up) at the alternator. Ran the 4 gauge cable from the alternator directly do the battery. Success!
Last step is to pull the O2 wiring from the factory positive battery cable loom and give its own loom, then tidy some things up with some zip ties.
If I could I would keep giving you more rep subford - it won't let me haha. Cheers mate.
Last step is to pull the O2 wiring from the factory positive battery cable loom and give its own loom, then tidy some things up with some zip ties.
If I could I would keep giving you more rep subford - it won't let me haha. Cheers mate.
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Remind me, did you fuse the line to the battery from the alternator with something like this? I thought you did but wanted to make sure because it's always a good idea.
I'm glad you got it working and I will be using your success to finish my own 130 amp conversion that I am about half way through. The only thing I might be doing differently after much reading is I don't think going directly to the battery positive is the best practice since 1. I want to properly fuse it. and 2. you apparently don't want a fuse burning to save the wires right by/on the battery because it might blow up the battery. So I will be going to a fuse holder mounted by the stater solenoid, to the solenoid, and then to the battery. Or perhaps just Alternator > Fuse> Battery and leave the factory positive from battery to solenoid.
I will be using this mounted right by the starter solenoid, however, I have seen other write-ups where people just mount the mega-fuse directly to the positive solenoid terminal.
Does this sound reasonable?
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