melted my jumper cables jumping my FJ.. wont jump.. wtf? (1 Viewer)

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so, my FJ would not turn over today. I guess the battery just go to low as I turned the key and nothing. 2.8 year old Red Top Optima and I have not driven her in a month given my busy schedule.

Anyway, no biggie as my buddy was over so we can just jump it. Got out the cables, he hooked them up and we went to jump it and the jumper cables started smoking at the connection points on both the FJ and the car - started to melt the plastic near the clamps. I have never seen such a thing. I looked at the cables and, not sure if it really matters, he had hooked up the ground to the (-) pole on the FJ battery and not grounded to the frame. I figured that was the issue. Well, I regrounded to the frame and same thing.

We went on to try this 5 times and every time - even with nicer 2nd pair of heavier gauge cables just to test - the moment I attach the ground on the FJ I get some sparks as I clamp to the frame and smoke starts to form (at connection in car and FJ) as the plastic melts and the cables and FJ battery get warm. and the car is not even running or turned on.

Is this a battery issue with the Optima or something bigger? I have a little device that I can stick into a cars lighter that gives you electrical system 4 light feedback - like if the battery is dead or low - and it does not even light up now. Turn the key, the AMP gauge does not even deflect. absolute 0 electrical activity.

WTF is going on? I have never seen this. Jumped cars many dozen of times before in minutes with never an issue. Plus, never had issues before like this with the FJ. Last time I drove it... zero issues. Just parked it inside.

FYI, 2 months ago I replaced the old starter and solenoid. but had driven it 10 times since I did that. and now.....
 
Optima's have a lower internal resistance than typical lead acid batteries, so it is possible that your severely drained Optima was accepting a charge at a higher rate than either pair of jumper cables could handle.

It is also possible that the battery malfunctioned and shorted out.

If it was me, I would look up Optima's charging instructions on their website and hook your optima up to a charger. Also, charging up dead batteries can be pretty tough on alternators.
 
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x2 on Cruisinga said, double check all the grounds points and re-cleaned again,scrap out paint or rust, upgrade negative cables and the + for better quality cables...welding 2 ga cables are very good
 
some basic charging data, but no jump insructions on their site.

cleaned both terminals, checked power cable at starter and ground on the engine block... all are clean and good... neg cables are fairly new and in great shape... that did not address the issue.

Seems I could go to harbor freight and get a 12v battery charger or maybe a float charger?

think any major damage was done to battery or other component like the solenoid? optima has a 3yr warranty.. I wonder if I should try to invoke that - I have 1 month to do so.
 
I would try to charge it with anything but a float charger.

I suggested the instructions because some "smart" chargers will not charge a dead gel-cell, because of their lower resistance, the charger thinks the battery isn't a battery. Their instructions explain how to get around this issue.

I don't see how you could damage your starter solenoid by jumping off your dead battery, even if the the jumper cables were smoking.
 
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Float charger from harbor freight says to not use on AGC battery,

Dumb question. What happens if you disconnect your battery and just jump to your cables from the other car.
That will eliminate your battery from being the prob.
 
Float charger from harbor freight says to not use on AGC battery,

Dumb question. What happens if you disconnect your battery and just jump to your cables from the other car.
That will eliminate your battery from being the prob.

you mean hook the pwr and ground cables from the Fj right to the jumper cables and then hook the jumpers to my car? essentially using the battery from the car?

is there not a risk then to my car?
 
also - using a test light, when I ground the test light on the - terminal, the + terminal barely triggers the test light - but it does trigger it. BUT, if I ground the test light to anything but the - terminal, I cannot trigger the light. only grounding to the - terminal... that is odd, no?

& multimeter shows 4.75 volts
 
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you mean hook the pwr and ground cables from the Fj right to the jumper cables and then hook the jumpers to my car? essentially using the battery from the car?

is there not a risk then to my car?

If you're worried, disconnect the cables from both batteries and jump from the good battery to the bad truck.
 
I would take the battery to Autozone or advanced auto and have them put it on their machine that tests battery. Unless your jumper cables were in real bad shape I bet your battery is bad. A month would not be long enough to drain a good battery unless you left something on. Likely the not able to start and not able to jump it are related to a bad bettery.
 
If you're worried, disconnect the cables from both batteries and jump from the good battery to the bad truck.

ahh... I see what your saying. yes, I could do that. at that point, might as well just take the battery out of the car and put it in the truck so I can get it back into the garage (we pushed it out to work on it).

BTW, I see no notation about the "AGC" float charger on HF website, but I will not buy it nonetheless.
 
I would take the battery to Autozone or advanced auto and have them put it on their machine that tests battery. Unless your jumper cables were in real bad shape I bet your battery is bad. A month would not be long enough to drain a good battery unless you left something on. Likely the not able to start and not able to jump it are related to a bad bettery.

I did not mention, I have a kill switch. that kill switch was set to off for the month. so technically, nothing should pull and drain it.

both sets of cables were pristine.
 
You have some kind or short; either the battery or the truck. Disconnect the battery and try jumping it. Also jump to the battery only. that way you will know whether the short is in your truck wiring or the battery. When you connect to the truck with everything turned off, there should be no sparks.
 
I bet your batter is shorted out then if the kill switch was off. Here in FL with the heat batteries can short and dies when not driving, good thing happens udually less then warranty period. Never had one smoke the cables, but have had them where you cannot even jump them at all. Usually goes from being a 100% good battery to a 100% bad battery instantly.
 
You have some kind or short; either the battery or the truck. Disconnect the battery and try jumping it. Also jump to the battery only. that way you will know whether the short is in your truck wiring or the battery. When you connect to the truck with everything turned off, there should be no sparks.

sorry, but how are these different "Disconnect the battery and try jumping it. Also jump to the battery only."?
 
I bet your batter is shorted out then if the kill switch was off. Here in FL with the heat batteries can short and dies when not driving, good thing happens udually less then warranty period. Never had one smoke the cables, but have had them where you cannot even jump them at all. Usually goes from being a 100% good battery to a 100% bad battery instantly.

when you have the kill switch off, the battery does not spark when you try to connect jumpers to it and the jumpers do not smoke and melt. The moment you turn the kill switch to live, that second the jumper cables start to smoke - even when cars not on - if the cables are already connected. if you try to connect them then, they spark. so the issue arises the second you are completing the ground to the vehicle with the switch.. does this imply it is in the trucks wiring or battery or undecided yet?

also, why can you only trigger the test light with the (-) battery pole and not any other ground in the rig? that seems illogical.

electrical is not my strong suit - just enough to be dangerous and get around at a better than basic level
 
do you have access to a dual color testlight? if so, test the polarity of the battery. it happens...i've got a agm battery with reversed polarity sitting on my driveway. took quite a while to figure out that one.
 
do you have access to a dual color testlight? if so, test the polarity of the battery. it happens...i've got a agm battery with reversed polarity sitting on my driveway. took quite a while to figure out that one.

do not have one.

reversed polarity - it seems that issue would raise it's head instantly upon putting the battery in.
 
when you have the kill switch off, the battery does not spark when you try to connect jumpers to it and the jumpers do not smoke and melt. The moment you turn the kill switch to live, that second the jumper cables start to smoke - even when cars not on - if the cables are already connected. if you try to connect them then, they spark. so the issue arises the second you are completing the ground to the vehicle with the switch.. does this imply it is in the trucks wiring or battery or undecided yet?

also, why can you only trigger the test light with the (-) battery pole and not any other ground in the rig? that seems illogical.

electrical is not my strong suit - just enough to be dangerous and get around at a better than basic level


your night switch is on the ground side ? , if so you won't have it light up unless the switch is on or you put it directly on the - terminal .

i think you have a big dead short in your wiring , one of the heaviest gauge wires you have most likely . it is grounding out , rubbed through or something . start at the battery + and work your way down till you find the melted / burned / grounded / wire .

if your night switch was on the + side i would of possibly blamed it but you are usuing it on the - side so there is nothing wrong with it .
 
do not have one.

reversed polarity - it seems that issue would raise it's head instantly upon putting the battery in.

not until your night switch is turned on .

a digital multi meter will also show polarity , if you hook the leads up backwards you will get - numbers . if you don't have one you can buy a cheap one for like 25$ its a better tool then a test light .
 

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