TZ Resetting

[pinball god]

First time come across such a problem. Switch the TZ on just now and the minute I press a flipper, it resets. Tried this several times with the same result. I then played for a little while without flipping and it went ok and could flip for a little while before resetting again. I know there has been some talk on such problems but don't know if applicable to this.

Any ideas on what needs replacing/fixing?
Thanks

[Strangeways]

Most likely the driver board needs the Caps and BRs replaced - more like a "preventative maintenance".. See my Addams Resto thread for more info

Could also be the fact that it is REALLY hot and if the machine is on the same circuit as air con etc - it may trigger a reset.

[MartyJ]

+1 for Nino's suggestion...Probably loosing 5v at the driver board.

Also check to make sure you havn't lost the diodes on that flipper coil.

[dj10555]

Another +1 for Nino. Changing the bridges and caps will fix 90% of reset faults. If it still continues after this, you could also measure your 5 volts and replace the 5v regulator if this is too low (below 4.92v). Not very common but I also had a game with the same fault and it turned out to be the bridge on the fliptronics board causing a reset.

[pinball god]

Most likely the driver board needs the Caps and BRs replaced - more like a "preventative maintenance".. See my Addams Resto thread for more info

Could also be the fact that it is REALLY hot and if the machine is on the same circuit as air con etc - it may trigger a reset.

I think you were correct. No problem todayafter getting in from work and no aircond going. Had a game without problems, but will keep an eye out for any further resets. Thanks guys

[ktm450]

More specifically Rob, the Bridge Rectifier you need to change is BR2 and while you have the board out you should change the associated C5 filter capacitor.
The PCB is printed on both sides so make sure you get a good solder flow on both sides (solder from both sides if you can) check your handy work with a multimeter to ensure a good join (both sides) and you wont have to worry about the jumpers a lot of guys recommend.

[pinball god]

More specifically Rob, the Bridge Rectifier you need to change is BR2 and while you have the board out you should change the associated C5 filter capacitor.
The PCB is printed on both sides so make sure you get a good solder flow on both sides (solder from both sides if you can) check your handy work with a multimeter to ensure a good join (both sides) and you wont have to worry about the jumpers a lot of guys recommend.

Thanks mate will give it a go in a few weeks as I'm banned from repairs until all my Open for Inspection days are done. The boss is non negotiable at the moment until the house is sold.

[johnwartjr]

4.92 is really on the low side of acceptable, especially for a game like TZ. I'd try to get it up to 4.95 or higher. Also check the 5 volts at pin 32 of the game ROM. Some games use an inline splice between the CPU and driver, and I believe TZ is one of them. That connector is notorious for causing a voltage drop.

Most people also don't replace C4, which costs about 25 cents and can make a sizeable difference in the +5.

On real problem boards, I isolate the case of the LM323 from the driver board, and install a 22 ohm 1/2 watt resistor between the case and ground. That bumps the 5 volts up to about 5.1-5.2 volts.