So I have a WPC game that keeps resetting.  I replaced BR1 and BR2, along with C5.  And ran jumpers and tested all connections.  Game still resets.  Looks like the 18v is low.  So off to replace some more parts.  It is also suggested to 'jumper' a lot of the BR's to their respection capacitors.  Just like this (from Marvin3m):



While I was working on the board, I was wondering if anyone has ever had to do this before?  And was it the solution?

My old TZ would reset randomly. I took some #14 green stranded wire and ran a ground from the switch box to the primary power connection up to the backbox and to each of the boards, with the power board having a termination on both sides of the board. Never reset again, solved all the random issues I was having.

Good to keep in mind.  My resets may be a grounding issue.

Check your thermistor in the power switch box in the cabinet.  These can go flaky and cause resets, just bypass the thermistor with aligator clips and test by playing.

Quoted from Monkeybug

So I have a WPC game that keeps resetting.  I replaced BR1 and BR2, along with C5.  And ran jumpers and tested all connections.  Game still resets.  Looks like the 18v is low.  So off to replace some more parts.  It is also suggested to 'jumper' a lot of the BR's to their respection capacitors.  Just like this (from Marvin3m):



While I was working on the board, I was wondering if anyone has ever had to do this before?  And was it the solution?

Check your wall voltage before anything else. You may have to lower the 5v watchdog circuit threshold. All voltages are derived by what the wall is putting out. If the input voltage is too low, the 5v watchdog circuit will cause resets.

Well I had some time to look at this problem again and this is what I found.

1. I replaced BR1 and BR2, and the 3 related 15k caps.
2. I did all the jumper mods according to Clay.

- Still reset when the flippers where pressed.  It would then just go in a continuous reset loop.  This was different.  I checked the voltages on the TP points and they were all good (while it was resetting).  I turned it off for 5 min.  Came back it was booted fine.

3. I checked the voltage.  Doh.  111v from my extension cord.  I was overlooking the obvious.  Tested the wall socket.  118v.  Ran a new extension cord.  118v.

- Still reset.  Same issues as above.

4. Checked thermistor.  After it warmed up, it was below 1v AC, so it looked good.  I decided to jump the thermistor with a clip, just in case.

- Still reset.  Same issues as above.

So now I think I will need to do a power board swap from a known good game (the advantages of having more than one of the same era/mfg of a game).

It may the the CPU board also, but I would ground the pin first. That solved my problem.

118 Volts generally will not be problematic on most games, but may I suggest if the board swap does not rectify your situation.

http://pdfserv.maxim-ic.com/en/ds/DS1811.pdf

If the power board doesn't solve the issue, try the CPU board as Enzo suggested, I have heard of issues that were solved by re-seating CPU chips. Also is there anything coincidental with the game that causes the resets? I.e. both flippers being engaged?

Another update.

1. Unplugged Sound board.  Still resets.

2. Unplugged DMD board.  Still resets.

3. Swapped CPU's, along with the rom.  Still resets.

4. Swapped Fliptronics board.  Still resets.

It always resets when the flippers are pressed.

Next attempts:

1. Cable swap
2. Check grounds.

After that... I am out of ideas.

Quoted from Monkeybug

After that... I am out of ideas.

for auction: R@RE UNTESTED VERY NICE (put game name here)

I bought it last week and had no time to plug it in for testing so i'm selling it as-is, untested.
Previous owner said it was resetting... it could only be a fuse !

Quoted from Azatotht

for auction: R@RE UNTESTED VERY NICE (put game name here)

I bought it last week and had no time to plug it in for testing so i'm selling it as-is, untested.
Previous owner said it was resetting... it could only be a fuse !

lol.... you forgot to mention HUO!

If it's a Rocky it doesn't need to be tested, because the buyer does not care.  

Check your coil diodes and measure your 5 volt supply under load.