Battery Sizzling

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Notacop

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Some of you may have seen my intro post yesterday, I picked up a 2013 PPV with 113k miles. After driving around for a bit, there was a bit of a rotten egg smell. Its not from the cat, instead it is coming from the battery on the passengers side. After driving, the battery itself was making a faint sizzling sound, almost as if the liquids in the battery were boiling. I have only experienced this one other time in the past, and it was due to a shop tech installing the alternator cables backwards and basically cooking the battery.

I do not believe this is the case here, I am leaning more towards a short, or something related to the removal of the police electronics. Below is a picture of the terminal currently. I plan on removing some fuses and seeing if the truck still operates normally. Hopefully this will reduce the load on the battery and eliminate any possible shorts.

Has anyone experienced this? What are my best options here? Can I remove the aux battery easily?

I am not the best with electronics in vehicles, but I don't mind giving it a shot.

Pic of terminal connection (passenger side battery)

Battery.jpg
 

Sparksalot

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Pull the negative cable off that one battery then see what happens in the next day or two. Are they currently a matching pair? Including age? That may be your issue.

In theothertwin, the battery in that position was shot, with 5 dead cells. I drove it a couple of months with that one disconnected, using just the second battery.

if you replace them, be sure the two new ones are matched.
 
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Notacop

Notacop

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Pull the negative cable off that one battery then see what happens in the next day or two. Are they currently a matching pair? Including age? That may be your issue.

In theothertwin, the battery in that position was shot, with 5 dead cells. I drove it a couple of months with that one disconnected, using just the second battery.

if you replace them, be sure the two new ones are matched.

So in theory, both batteries should be able to work independent of each other? I was going to remove some of the fuses on the battery and see how far I could get with the truck still starting, but if I can remove the whole thing and it still works I will do that for now.

I am not sure of the age of either, but I will plan on replacing both at the same time for sure.

Thank you!
 

Sparksalot

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Most of the time the batteries are in parallel without an isolator. Both of mine are that way. They will start and run on either one individually.

BTW, the fuses on the battery terminal are purely for the auxiliary PPV systems. They can all be removed are normal operation of the basic truck is not affected.
 

Sparksalot

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Do you have anything mounted on the bracket where the hood strut is? I’m not positive, but I believe that is the spot where an isolation relay would be mounted if there is a factory battery isolator.

A2AD2FF5-05A5-404E-B4AF-D6848E8C4CC4.jpeg
 
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Notacop

Notacop

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Most of the time the batteries are in parallel without an isolator. Both of mine are that way. They will start and run on either one individually.

BTW, the fuses on the battery terminal are purely for the auxiliary PPV systems. They can all be removed are normal operation of the basic truck is not affected.

Good to know! thanks again
 

Bill 1960

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Sounds like a dead cell. That can short out so the battery is now essentially a 10 volt battery with the cells remaining. Now it’s being overcharged on the still working cells and that causes the smell and sizzling.
 

Sparksalot

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Most of the time the batteries are in parallel without an isolator. Both of mine are that way. They will start and run on either one individually.

BTW, the fuses on the battery terminal are purely for the auxiliary PPV systems. They can all be removed are normal operation of the basic truck is not affected.
@Notacop let me amend that. The 175amp fuse is the connection point of the auxiliary battery. The 125 and 60 are the auxiliary power systems in the cabin.
 

petethepug

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On our Audi we had the identical symptoms you described. It turned out to be the battery post diameter on an Optima yellow top. It was slightly smaller than any battery I had used in the past and it would not clamp down and make good contact on the positive cable on the battery.

It overheated the + cable, melted part of it and that created a huge resistance in the path. Between the ill-fitting + post on the Optima and the crispy fried wire it heated up the battery AND the wire until it blew a heavy duty fuse in the + battery cable. It gave off the rotten egg smell and sizzled the sealed battery too.

Not sure what your’s is doing but give it a careful twice over before the battery off gasses and blows up.


Sent from my iPhone using Tapatalk Pro
 
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Notacop

Notacop

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Do you have anything mounted on the bracket where the hood strut is? I’m not positive, but I believe that is the spot where an isolation relay would be mounted if there is a factory battery isolator.

View attachment 275541


I'll have to look when I get home. 3 cables run along the firewall, 1 goes to the fuse box, the other two pass through some sort of relay before heading into the cabin. There is a fourth that looks like it goes to the alternator.
 
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Notacop

Notacop

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On our Audi we had the identical symptoms you described. It turned out to be the battery post diameter on an Optima yellow top. It was slightly smaller than any battery I had used in the past and it would not clamp down and make good contact on the positive cable on the battery.

It overheated the + cable, melted part of it and that created a huge resistance in the path. Between the ill-fitting + post on the Optima and the crispy fried wire it heated up the battery AND the wire until it blew a heavy duty fuse in the + battery cable. It gave off the rotten egg smell and sizzled the sealed battery too.

Not sure what your’s is doing but give it a careful twice over before the battery off gasses and blows up.


Sent from my iPhone using Tapatalk Pro


I'll keep that in mind as well, it does have some crazy terminal splitter (see original post) so its possible the size is a bit off.
 

Sparksalot

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I'll have to look when I get home. 3 cables run along the firewall, 1 goes to the fuse box, the other two pass through some sort of relay before heading into the cabin. There is a fourth that looks like it goes to the alternator.
If you’re referring to the two black inline connections, those are just single straight blade connectors. I had to rebuild the 125 amp cabin feed on thecopcar, so got kinda familiar with them. I never did rebuild the 60 amp feed, but used that fuse to run separate feeds directly to some ham radio gear.

7A15A966-12C7-457C-B8B0-8E73CE477902.jpeg D635475F-62B6-4FA7-88D4-06BF2B48F910.jpeg
 
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Notacop

Notacop

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Pull the negative cable off that one battery then see what happens in the next day or two. Are they currently a matching pair? Including age? That may be your issue.

In theothertwin, the battery in that position was shot, with 5 dead cells. I drove it a couple of months with that one disconnected, using just the second battery.

if you replace them, be sure the two new ones are matched.


I disconnected the problem battery last night and it didnt start. Im just going to replace both batteries and hopefully that resolves the issue. What do you mean be sure they are matched? I've never owned a vehicle with two batteries before so I am not familiar with what to look out for.
 

Sparksalot

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I bet your second battery is already toast.

If you buy two of the same batteries at the same time and place you’re good. If one place only has one, don’t snag it then buy another elsewhere or at another time.

I replaced a pair with new AGM batteries a few months ago, and found that batteries plus and Walmart were the least expensive choices for me.
 
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Notacop

Notacop

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I bet your second battery is already toast.

If you buy two of the same batteries at the same time and place you’re good. If one place only has one, don’t snag it then buy another elsewhere or at another time.

I replaced a pair with new AGM batteries a few months ago, and found that batteries plus and Walmart were the least expensive choices for me.

Gotcha. Thanks for the tips. I have a feeling one is already dead also, it hesitated on startup once or twice. Fingers crossed replacing both does the trick...I was supposed to buy rubber floor mats with this money haha.
 

Bill 1960

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For ordinary use, why not delete the second battery? Double the cost for no benefit.
 

RichardCranium

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Just be really careful, especially since that battery has already shown a defect of sorts (no matter what the causation, the battery has been pushed through its paces it is boiling). A battery can very easily explode, which means chunks of plastic shrapnel everywhere, and more importantly that means battery acid everywhere. I'd at least wear safety glasses and nitrile gloves. Coming from someone who worked 15+ years in the automotive repair field, I've seen this happen several times (witnessed it once).

Wearing the safety hat for once, not too often I do. :)
 
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Notacop

Notacop

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For ordinary use, why not delete the second battery? Double the cost for no benefit.

Is this easy to do? I am not electronically savvy. Is it as simple as not re-installing the second battery, or more involved than that? @Sparksalot is correct, this will be a daily/baby hauler for the wife.
 

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