battery isolator question
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Thanks again for all the good suggestions! joshofalltrades, you hit the nail on the head as when I couldn't get anything on the key, I removed the A cable and put it on the 1 post. Started right up, but I basically just bypassed the isolator in a sense. I see the point about the jump wire giving a path to bypass the isolator as well, so won't do that. I'm sure it's something stupid I'm not seeing that's right in front of me 
As of right now, batteries are charged, alt outputs correctly, all is normal until I put that isolator into the system. My 12v source for the exciter terminal is from the fuse panel, which is the newer style blade fuses fwiw.
As of right now, batteries are charged, alt outputs correctly, all is normal until I put that isolator into the system. My 12v source for the exciter terminal is from the fuse panel, which is the newer style blade fuses fwiw.
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this is all making sense to me. the wire you're moving to the A terminal of the isolater contains more than just the alternator output, it also powers critical vehicle functions. try this - NEW charge wire from alternator to A terminal of isolater, alternator end of old charge wire to 1 terminal of isolater, and starter solenoid end of old charge wire to starter solenoid (battery).
that should solve everything right there
that should solve everything right there
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this is all making sense to me. the wire you're moving to the A terminal of the isolater contains more than just the alternator output, it also powers critical vehicle functions. try this - NEW charge wire from alternator to A terminal of isolater, alternator end of old charge wire to 1 terminal of isolater, and starter solenoid end of old charge wire to starter solenoid (battery).
that should solve everything right there
that should solve everything right there
So do you think I even need the exciter?
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It depends on the vehicle if it needs the exciter terminal or not. I have both isolators now so I'm covered either way, lol! Can anyone tell me what the other two wires are that plug into the alternator? (see original post)
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the two small wires on the alternator are the ones that control it. one is always hot and is the voltage sensing wire, telling the alternator how much to charge. the other is a switched hot, and switches the alternator on and off when the key is on/off. i don't see any reason for you to have to change them.
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I ran a wire from the battery +ve to the exciter post on the isolator and away she went. But, all my instructions say to run it from a "hot run" source at the fuse panel. I couldn't find any??? Any more suggestions? Is it ok to leave it right from the battery? Seems like it wouldn't be otherwise they'd have put it in the instructions, lol!
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i'm not sure exactly how the isolater is set up, but i suspect that when the exciter terminal is hot, the isolater consumes a small amount of power, and thus will drain the battery overnight. it may also trigger a relay that connects the two batteries to each other.
you should be able to tap it in to the switched hot wire that turns on the alternator and have it working that way
you should be able to tap it in to the switched hot wire that turns on the alternator and have it working that way
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From: Virginia
You can't leave the exciter wire hooked up to the battery. This Ford alternator from what I am reading doesn't even need the exciter hooked up. But if you want to hook it up, it has to have key-on power only.
Why haven't you re-wired it to make it work? Take the large output wire off the alternator and tape it, insulate it. Make sure all the other wires are hooked back up like they are supposed to be. Then try to start it. It should start right up, but not charge.
Cut the engine off, get a new fat wire and run it from the alternator to the isolator"A", hook the rv wire up to the isolator "2", and then run a new fat wire from the battery terminal"1" on the isolator to the battery + under the hood, either to the battery directly or the large solenoid connection that goes to the battery. You should be good to go then.
Why haven't you re-wired it to make it work? Take the large output wire off the alternator and tape it, insulate it. Make sure all the other wires are hooked back up like they are supposed to be. Then try to start it. It should start right up, but not charge.
Cut the engine off, get a new fat wire and run it from the alternator to the isolator"A", hook the rv wire up to the isolator "2", and then run a new fat wire from the battery terminal"1" on the isolator to the battery + under the hood, either to the battery directly or the large solenoid connection that goes to the battery. You should be good to go then.
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Ok, the only thing I haven't done is use a new cable from the alt to the A post on the isolator. I don't understand what difference it will make but I will try. I trust your experience I do have a new wire from the solenoid to the 1 terminal already and the 2nd battery to the 2 terminal. I only reused the original BK/OR cable from the alternator and ran it to the A terminal. I'll post back after I get the new cable on. Thanks!
I do have a new wire from the solenoid to the 1 terminal already and the 2nd battery to the 2 terminal. I only reused the original BK/OR cable from the alternator and ran it to the A terminal. I'll post back after I get the new cable on. Thanks!
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we're asking for a new wire there because the old one powers other circuits on the vehicle, thus causing your problem when its disconnected by the isolater. review post #17 above, wire it as such, and i believe your problem will be a thing of the past.
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The young grasshopper is learning!!! You're right. All is calm in my RV world now. Works like it should Many thanks and much appreciation for your patience guys! I can't tell you how many times I've read and re-read this thread and "just" get it now. The whole family thanks you for the working 12v stuff in the "house on wheels"
Many thanks and much appreciation for your patience guys! I can't tell you how many times I've read and re-read this thread and "just" get it now. The whole family thanks you for the working 12v stuff in the "house on wheels"
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hey not to hi-jack here, but this is what I am looking for. I have an 94 explorer. Can you use the standard 3leg isolator with this isolator, or do you need to have one with exciter wire? I have an old thread ive updated now that I actually have a truck now
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From: Virginia
You should be able to use the regular 3 leg isolator.
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So I just tried it being I am having a separate issue with is bucking while driving. Was thinking fuel pump is going but the relay on that is burned abit (another thread, another day) anyways so far just running alt to center leg and main battery to batt1 is charging and so far the only vehicle I successfully been able to use this on .. Thanks a bunch.. now where to mount as there isn't much room under the hood and a long cable to the cabin from alternator isn't good either
At any rate thanks for confirming
.. Thanks a bunch.. now where to mount as there isn't much room under the hood and a long cable to the cabin from alternator isn't good eitherAt any rate thanks for confirming
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