Electrical issues after dead battery

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I recently took my 80 out for a drive and everything worked great. After I was unaware that my kiddo left the rear door slightly open which drained my battery. I jumped the battery and got it running. I took it out for a drive and it had no blower fan, no power windows, sun roof didn't work, none of the gauges worked either. Power locks and radio still worked, power seats move (as good as they can without new worm gears). I came to a red light and it almost died at the first red light. I bought a new battery and it runs but with the same electrical problems. I checked all of the fuses in the knee panel and under the hood near the battery they all looked good. Any thoughts or suggestions? Fusible links? bad ground?
 
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I recently took my 80 out for a drive and everything worked great. After I was unaware that my kiddo left the rear door slightly open which drained my battery. I jumped the battery and got it running. I took it out for a drive and it had no blower fan, no power windows, sun roof didn't work, none of the gauges worked either. Power locks and radio still worked, power seats move (as good as they can without new worm gears). I came to a red light and it almost died at the first red light. I bought a new battery and it runs but with the same electrical problems. I checked all of the fuses in the knee panel and under the hood near the battery they all looked good. Any thoughts or suggestions? Fusible links? bad ground?
What's the voltage at with the new battery and the engine turned on?
 
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Did you test your fuses ? Under hood and inside? Many pass visual but don't pass continuity.
The guage fuse (10A) was blown and I replaced with 15A to see what would happen. It immediately blew the 15. all the fuses under the hood tested fine
 
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Ok so your alternator is working and seems like the voltage regulator is alright. Looks like you have the fun job of chasing down your short on the gauges circuit. All the stuff you describe as not working is on that circuit. If it instantly pops the fuse then there's a direct short. Is the cigarette light working?
 
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Ok so your alternator is working and seems like the voltage regulator is alright. Looks like you have the fun job of chasing down your short on the gauges circuit. All the stuff you describe as not working is on that circuit. If it instantly pops the fuse then there's a direct short. Is the cigarette light working?
yes the lighter is working. Other things that work: horn, wipers, dome light, headlights, tail lights, turn signals all working. really weird. I guess I'll start checking my wiring diagram?
 

clx16

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So i am going to ask a question that i should look up but i am under the weather. is the blown fuse from the box under the hood or in the cab? if under the hood then you can look to see which fuses it protects in the cabin and and you can go with a test light. clamp on 12+ and the light probe hit the fuses in the cab to see which one lights it up since one of the fuses will be grounded. that can narrow it down to the right circuit. Obviously the wiring diagram will explain from a more scientific process.
 
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So i am going to ask a question that i should look up but i am under the weather. is the blown fuse from the box under the hood or in the cab? if under the hood then you can look to see which fuses it protects in the cabin and and you can go with a test light. clamp on 12+ and the light probe hit the fuses in the cab to see which one lights it up since one of the fuses will be grounded. that can narrow it down to the right circuit. Obviously the wiring diagram will explain from a more scientific process.
It's in the cab
 

clx16

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OK so i would take two tiny spade connectors and stick them on each side of the fuse receptors where the fuse was at. I would connect those to a multi meter and expect it to show the voltage approx the same as the battery. I would remove a few panels, kick panel, knee basher panel etc and i would shake those wires and see if the voltage drops out when you shake certain wires. No that is what i would do and realize i am sick so maybe not do it and let someone else give you a better method. Personally I usually pull the dome fuse when i am doing that just to save the battery all the pull with the doors open etc.
 
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so you're saying shaking it isn't a good idea? :rofl:. Any suggestions on where to start?
The Toyota EWD is where I would start along with a multimeter. Section H, page 42-49 lays out every fuse and associated circuits.
@clx16 had a good idea to use a spade connector on the load side of the fuse. Attach one of the meter leads to that with the other on a good ground. You appear to have a direct short since the fuse pops immediately. If your meter has a continuity beep it would make it easier to locate. At least this way you're not popping fuses.
 

LINUS

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@ATEAm - what yr 80 is it?

That portion of the harness is broadly the same across all 80’s save a few updates, but at least in my case, I have had 3) late OBD2 80’s so that’s what my wheelhouse is.

From memory the biggest change in late OBD2’s is the jump from ‘Yota to Lexus in the HVAC/climate control - but it’s been since Obama that the LX450 sold.

Do you have a EWD or do you need to source one?
 
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@ATEAm - what yr 80 is it?

That portion of the harness is broadly the same across all 80’s save a few updates, but at least in my case, I have had 3) late OBD2 80’s so that’s what my wheelhouse is.

From memory the biggest change in late OBD2’s is the jump from ‘Yota to Lexus in the HVAC/climate control - but it’s been since Obama that the LX450 sold.

Do you have a EWD or do you need to source one?
I have one for the 1996. Is the EWD the same for 1995?
 

LINUS

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I have one for the 1996. Is the EWD the same for 1995?
I think some wires changed going to the cluster when they did the facelift 96-97 dash from the ‘Enterprise‘ dash.

-Does your dash have a ‘squared’ shape around the cluster, or does it sweep over the top the stereo/HVAC area?

- aside from that ‘95 was the transition yr for the AFM / MAF underhood & trans & FF RR axle IIRC. (stuff not important today)

But if you have a late ‘95 build/dash - the ‘96 EWD ought to be right. Frankly, I’m not sure where the split was between the 2 dashes in ‘95.

If you have the ‘sweep’ dash, you might search if there’s a link for the ‘95 EWD.
Build date is on the DR door sticker with all the build detail like tranny code / lockers & R&P, etc.
Best place to start to identify if you’re not sure.
 

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