ToM on fire!!

[pinball god]

Replaced the batteries just nowon all my machines as a precaution. Could smell an electrical smell. Turned all machines off and checked batteries. Noticed on ToM that it has an external type battery pcb and eventhough I thought it strange prior to replacing +-+ I checked the pcb and it shows +++. I put he batteries +++ but still see fine smoke coming from machine.

Can incorrectly putting on batteries cause such a problem & if so where abouts?

All the other machines have pcb mount batteries +++.

Have I f**ked up big time or not? Thanks

[indazone gav]

Sounds more like a popped capacitor mate. probably nothing to do with the batteries at all.

[pinball god]

here are some pix of the pcb...ooooooops F109 is fried. What can I do or try?

have a look at the fuse I've never seen something like this before. just checked and the fuse isa 5A sb and still reports ok for continuity and connrction to J115-4 seems still ok however there appears some burning runnimg towards R10, Q11, Q12 but I think this is not causing any problems. So will resoldering the fuse holder and replace the fuse be a wise move at this moment?

[Strangeways]

I'm seeing some "burn" marks between the fuse holders in the first picture.

Check J115 connector for burn marks. Could be a fried connector.

[pinball god]

had a good think about the pcb last night and conclusion is changing battery not the cause. I think this is an inherent probelms with the pcb. A bit of background on this pcb. After short time of purchase GI#2 (back board lights) went down and tech came to fix. Had no problems until long while later I noticed one globe missing and replaced it. No problems. Then one day I left the machine running for lets say 3-4 hours and then noticed GI#2 out.

I then posted on AA the problem and could not solve it. So got a tech in who couldn't solve it on site. Was reported to be a bad solder joint on F109. Machine has worked fine until now some say 2 months. BUT....the machine is only on for short bursts of say a game or two at a time. On Saturday night I had a party and all my machines were on for at least 5 hours or so.

I reckon ToM was slowly cooking and everyone was too tanked to notice. So when I replaced the batteries last night ToM fried a bit more until she started smoking a bit. Like I say its was still working ok prior to switching it off last night but I'm guessing she'd continue to fry until GI#2 goes again.

So any ideas on what could be sending so much heat down the line?

I notice there are a couple of heavy gauge wire fixes going to J120-8 & F109 (opposite to burnt end) also J120-7 & F110 making me think this problem is not a first timer. You can see one of these wires in my picture above that goes to F109 (green). What's your ideas?

[Strangeways]

Has J120 Connector and pins been replaced ?

Remove the connector and see if the pins are tarnished.

[pinball god]

thanks Nino, the plug etc has been replaced not long ago and looks fine. I'll run this passed you though. The burn looks like the type that is caused by a back connection ie the fuse holder. I alo asked a sparky today who was looing at a job for me and he's thinking the same. If this is a possibility IYO or anyone elses, I thnking to solder a bridging wire from the burnt fuse pin to J115 to possibly aid in 1. the connection and 2. take some of the amperage/heat from the track that my be weakened.

Is my thinking correct or not? What would cause the fuse to basically melt inside and keep working as opposed to blow. Is it voltage or amps that does this?

Thanks and I wait until I hear from someone before soldering.

[MartyJ]

Wow!  I've never seen a fuse do that before!

Just asking a silly question, is the correct SB fuse in place?

If you have a DMM with continuity setting, you can buzz the tracks from the fuse connector to make sure they are OK..

I can only think that heat - and lots of it caused an issue like that.  Are you getting the correct voltages?

[pinball god]

Wow!  I've never seen a fuse do that before!

Just asking a silly question, is the correct SB fuse in place?

If you have a DMM with continuity setting, you can buzz the tracks from the fuse connector to make sure they are OK..

I can only think that heat - and lots of it caused an issue like that.  Are you getting the correct voltages?

We gotta stop meeting like this Marty!!! I thought +1 about fuse rating but checked and is ok. I buzzed tracks and ok. A sparky said to me poor connection can cause such heating but he's no pinball tech. Tha's why I'm thinking about improving the connection with a wire as opposed to the track alone. The pcb has one of these on the other end of the fuse holder see picture. Unsure about voltages as the moment

[ajlaird]

Wow!  I've never seen a fuse do that before!

Just asking a silly question, is the correct SB fuse in place?

If you have a DMM with continuity setting, you can buzz the tracks from the fuse connector to make sure they are OK..

I can only think that heat - and lots of it caused an issue like that.  Are you getting the correct voltages?

We gotta stop meeting like this Marty!!! I thought +1 about fuse rating but checked and is ok. I buzzed tracks and ok. A sparky said to me poor connection can cause such heating but he's no pinball tech. Tha's why I'm thinking about improving the connection with a wire as opposed to the track alone. The pcb has one of these on the other end of the fuse holder see picture. Unsure about voltages as the moment

Yeah, if the connection is poor then this can cause such a problem, as basically the same current has to run through a smaller area hence heating it up more than usual. I would try the wire.

[Strangeways]

Wow!  I've never seen a fuse do that before!

Just asking a silly question, is the correct SB fuse in place?

If you have a DMM with continuity setting, you can buzz the tracks from the fuse connector to make sure they are OK..

I can only think that heat - and lots of it caused an issue like that.  Are you getting the correct voltages?

We gotta stop meeting like this Marty!!! I thought +1 about fuse rating but checked and is ok. I buzzed tracks and ok. A sparky said to me poor connection can cause such heating but he's no pinball tech. Tha's why I'm thinking about improving the connection with a wire as opposed to the track alone. The pcb has one of these on the other end of the fuse holder see picture. Unsure about voltages as the moment

Yeah, if the connection is poor then this can cause such a problem, as basically the same current has to run through a smaller area hence heating it up more than usual. I would try the wire.

I'd run another wire from the fuse holder to the corresponding pin on the connector.

The burnt track would not be a suitable conductor of current from the fuse to the connector..

[pinball god]

Thanks guys will do. Also thanks for the explaination of why it would burn. I didn't consider the path on the poor connection would be a restriction in current flow hence the extra load. Pretty obvious when you think about it.

[pinball god]

Just completed the re-wire and machine operates fine BUT just in the time it takes to re-enter all the settings, and a quick game (plunge, a few flips, let the ball drain 3 times), turned the machine off and felt the area of F109, F110 and its real hot to touch. If you leave you finger on there for more than a second, I reckon you'll get a good burn. So I believe this area would still cook if left on too long.

Any ideas on what next to do? Please advise on whether to take some kind of voltage reading at the fuse or something. What setting for the DMM etc etc. Thanks in advance

[ajlaird]

Check the other tracks in the area - you may want to bypass them with a rewire as well.

[pinball god]

Thanks mate, just pulled the board out again to check my re-wire and it looks ok. I thought maybe the insulation might be hard or burning off but its ok.