For starters i have a Oct '71 fj40. i went to start it today and it was completely dead. i turned the key to run and the coil didn't even click. the battery is good and is fully charged. the lights, windshield wipers, and everything else didn't work at all. i was able to put the key in run and start it by putting a wire from the battery positive terminal to the small wire on the starter beneath where the main lead attaches. i also hotwired the coil. once it was running the lights and everything but the voltmeter in the dash seemed to work allright. i turned it off and it immediately stopped as it should but the initial completely dead scenario returned. does anyone have any ideas what my problem might be? i'm thinking ignition switch but it doesn't make complete sense. thanks a lot
Electronic problem, not complicated just confusing (1 Viewer)
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Re: Electronic problem, not complicated just confu
me too. Your ignition switch is *probably* either dead, or there is a loose wire in there somewhere. I am willing to bet in fact that is it. It would make sense that the accessories work but the ampmeter (do you have an aftermarket voltmeter?) does not. Your alternator might not have been charging, since it requires a hot wire from ignition to begin charging. It is fairly confusing, but it seems to all be inter-related. Start with the ignition switch checking continuity and work your way to the starter, alt, and so on. You will want to buy at least a Haynes or something with good elec diagrams as this will make this work MUCH easier. Good luck, let us know what you find.
me too. Your ignition switch is *probably* either dead, or there is a loose wire in there somewhere. I am willing to bet in fact that is it. It would make sense that the accessories work but the ampmeter (do you have an aftermarket voltmeter?) does not. Your alternator might not have been charging, since it requires a hot wire from ignition to begin charging. It is fairly confusing, but it seems to all be inter-related. Start with the ignition switch checking continuity and work your way to the starter, alt, and so on. You will want to buy at least a Haynes or something with good elec diagrams as this will make this work MUCH easier. Good luck, let us know what you find.
Re: Electronic problem, not complicated just confu
suonds like your not getting power to the ign sw. i dont see any fuses or fuse links between sw and batt but that dosent mean there inst one. ps. there are color wirring diagrams on the tech page not sure about your year though. good luck
suonds like your not getting power to the ign sw. i dont see any fuses or fuse links between sw and batt but that dosent mean there inst one. ps. there are color wirring diagrams on the tech page not sure about your year though. good luck
Re: Electronic problem, not complicated just confu
Usually this type of problem is in the main feed line from the battery to the fuse block; commonly right where it connects to the battery post. May also be the fusible link as previously noted.
Usually this type of problem is in the main feed line from the battery to the fuse block; commonly right where it connects to the battery post. May also be the fusible link as previously noted.
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Re: Electronic problem, not complicated just confu
the fusible link? the only thing connected to the positive terminal is the wire that runs straight to the starter. i was suspicious of this at first but i checked the haynes wiring diagram and that is correct for my year. i'll pull out the ignition in the morning and let you guys know what i turned up.
the fusible link? the only thing connected to the positive terminal is the wire that runs straight to the starter. i was suspicious of this at first but i checked the haynes wiring diagram and that is correct for my year. i'll pull out the ignition in the morning and let you guys know what i turned up.
Re: Electronic problem, not complicated just confu
No fusable link until later 70s FJ40s.
No fusable link until later 70s FJ40s.
Re: Electronic problem, not complicated just confu
It sounds to me like the main feed wire to your fuse block is disconnected in some way. at the least the lights should work without the key.
It sounds to me like the main feed wire to your fuse block is disconnected in some way. at the least the lights should work without the key.
Re: Electronic problem, not complicated just confu
I had a similar problem on my '79 years ago when I lived back east. Turned out there was enough corrosion up inside the positive battery lead I couldn't get any juice to the starter.
I had a similar problem on my '79 years ago when I lived back east. Turned out there was enough corrosion up inside the positive battery lead I couldn't get any juice to the starter.
Re: Electronic problem, not complicated just confu
If you have power to the ign switch, it's the switch, otherwise it could be the fusable link or goofy wiring problem. The switches are pretty common failures. I have 4 columns without ign switches in them here at the shop.
If you have power to the ign switch, it's the switch, otherwise it could be the fusable link or goofy wiring problem. The switches are pretty common failures. I have 4 columns without ign switches in them here at the shop.
