MPU Battery Explosion!!

MC35

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So last night after palying a few times on my pinball I decided to watch a movie in my living room. The pin was still powered up. After about an hour my wife and I heard a bang comming from the basement, then the pin rebooted. We went downstairs to see smoke. I immediately unplugged Mata Hari and investigated.

The attached picture is what I found. Now all I get is general illumination lights and the LED is solid. This is a -17 Bally MPU. I just bought the MPU about 2 months ago and I haven't done any work to the MPU itself. Is this salvagable.
 

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So last night after palying a few times on my pinball I decided to watch a movie in my living room. The pin was still powered up. After about an hour my wife and I heard a bang comming from the basement, then the pin rebooted. We went downstairs to see smoke. I immediately unplugged Mata Hari and investigated.

The attached picture is what I found. Now all I get is general illumination lights and the LED is solid. This is a -17 Bally MPU. I just bought the MPU about 2 months ago and I haven't done any work to the MPU itself. Is this salvagable.

Let me guess......is there an Eldorado Games repair tag on the PCB?

Some dumbass install a non-rechargable lithium battery in a circuit that CHARGES.

Trying to charge ANY non-rechargable battery will (eventually) end in explosion.

Edward
 
That battery looks a lot like the 3.6V batteries in my wireless alarm sensors. They are NOT rechargeable.
 
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Yea, that's definitely not a factory battery.

The first thing you need to do is pull the board, and get some vinegar and clean it thoroughly to neutralize any of the electrolyte that may have spilled, or else it will go up the traces and wipe out components.
 
As a repair guy, stuff like this makes me want to vomit, and when I'm done with the vomit it makes me want to slap somebody. Sticking a non-rechargeable lithium into a bally board? I can see not wanting to put a new ni-cad in there, but either go with a non-volatile RAM or a memory capacitor. You're lucky that's all that happened, you could have potentially had a fire to deal with.

The good news is that it should be repairable without an issue. Just don't go anywhere near whoever did that install. I'd offer to do it myself, but I just don't know that generation Bally board enough to work on it, and don't have the equipment to test it properly.

-Hans
 
I have a friend who's gotten pretty good at those Bally 17's. I'm sure he'd repair it and bench test it cheap. He did my Harlem Globetrotters and KISS boards, as well as his own Flash Gordon board, complete with awful battery acid damage. I'm sure he could set you up.

Shoot me a PM if you want me to have him get in touch with you.

-Brad
 
Yea, that's definitely not a factory battery.

The first thing you need to do is pull the board, and get some vinegar and clean it thoroughly to neutralize any of the electrolyte that may have spilled, or else it will go up the traces and wipe out components.

If it's a lithium, don't you use baking soda on them? Not sure if they are an acid or a base.

-Hans
 
As a repair guy, stuff like this makes me want to vomit, and when I'm done with the vomit it makes me want to slap somebody. Sticking a non-rechargeable lithium into a bally board? I can see not wanting to put a new ni-cad in there, but either go with a non-volatile RAM or a memory capacitor. You're lucky that's all that happened, you could have potentially had a fire to deal with.

The good news is that it should be repairable without an issue. Just don't go anywhere near whoever did that install. I'd offer to do it myself, but I just don't know that generation Bally board enough to work on it, and don't have the equipment to test it properly.

-Hans

Sadly, all they would have had to do is remove one resistor.....and replace it with a 2¢ diode (if they wanted to go the route they did).

Edward
 
If it's a lithium, don't you use baking soda on them? Not sure if they are an acid or a base.

-Hans

I'm not for sure, but I can tell you this.......you need to act fast! I recently had a customer drop off a Pole Position board......he told me it exploded. Well, wouldn't you know it.....someone (RE: Eldorado) installed a non-rechargable lithium battery without disabling the charging circuit. He left the PCB set for a week before bringing it into the shop. It was non-repairable. The goo from the battery had literally ate everything it touched.....componets, traces, copper, substrate.....I'd never seen anything like it.

I recently had another customer bring in a Pole Position board for repair. He told me he'd gotten it back from Eldorado about 4 months ago. Guess what it had on it.......A nice fresh, brand new lithium battery....and the charging circuit was still enabled! IDIOTS! Needless to say, I removed it before it had a chance to blow.

Edward
 
Then clean it again.

repeat a few times.

You seriously can't clean this one enough.

-Hans

I can tell the traces under the battery and around the battery are fairly damaged. Not sure if vinegar alone will take care of this. Suggesstions?

I have attached before and after pics.
 

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If you bought it 2 months ago, and it really was from Eldorado, IIRC they have a 90 day warranty?

Try to get a replacement, let them know what happened, and if it has another lithium on there rip it off as soon as the replacement arrives.

-Hans
 
I would also pull the chips and carefully clean the legs ad then swab that whole area down with 90% Isopropyl alcohol. Vinegar will neutralize the battery electrolyte and the alcohol will dissolve it better than water to get the last of it out.

From the pictures it looks like the socketted chips are already starting to corrode though, so you need to pull them and vinegar wash and alcohol wash to stop any further damage.

ken
 
At this point I'm not ready to disclose where I bought this from, if the customer service turns out to be not so customer focused then I will.
I will be contacting the place I got it from and asking them what to do next.

I did replace the 3.3K ohm resistor that was affected, but still all I get when I power it up is a solid green LED.
Will the MPU power up and play without the battery?
 
I can tell you just from this thread that the "City of Gold" isn't going to be the "City of Repairs" for any future needs I might have, lol. If it's them, not sure it's going to further taint anyone's opinion more than it already is...if not, well..okay, I could see you giving them a chance to make it right since it MIGHT be a legitimate error.....albeit a pretty bad one. :p
 
From the pictures it looks like the socketted chips are already starting to corrode though, so you need to pull them and vinegar wash and alcohol wash to stop any further damage.

ken

Yeah, it looks like the 6821 took a descent hit....I'd replace the sockets too.

If you don't get all that shit off there (or neutralized good)....it's going to keep on eating.

For the record....I only know of two dip-shit places that use non-rechargable batteries in a charging circuit (and don't disable the charging circuit)....

01- Eldorado
02- Some idiot out of Texas (sorry, I can't remember his name....it's been awhile)....He used to (maybe still does)....run Ebay auctions for repair.

Edward
 
So once I de-solder the battery and clean it with vinegar, what's next?

use water to rinse the vinnegar, then rubbing alcohol 70% or so to help displace the water, then set a fan near it to help dry, or if you have access to air compressor.
 
How about the solid green LED, is that an indication that something is fried, or is it solid because it has no battery now?
 
I second Hans' recommendations - you will want to clean it multiple times.

What I would do after that is attach either a memory cap or an external battery pack with a diode in the circuit.

What I've done is make up a bunch of external battery packs that I mount to the inside of the cabinet with velcro. I wire a diode in series and use them for a wide variety of games.
 
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