Hello there,

Sorry for the long post.

I'm having problems with my T2. It's is my only pinball. I've owned it for about 15 years. I had one problem (repairs to cpu board due to battery corrosion) 5 or 6 years ago which was fixed by sending it out for repairs.

I recently moved across state, and when I fired up the pinball at the new house, my sound board fried. Since my finger was still on the switch I turned it back off. No fuses were blown anywhere. After seeing clear damage on the sound board, I removed it. I turned it back on, but it did not turn on all the way, and it resets the circuit breaker in the house about 50% of the time the switch is turned on. I'm not sure if that's caused by the new house I live in, or whatever is wrong with the machine. I measured 122v at the socket.

When it does partially turn on...
The DMD gets a bunch of garbled data on it.
The backbox/playfield do not light up.
Nothing moves or indicates it's on other than the hum of the transformer, DMD garbled data, and LEDs on the circuit boards.
CPU Board LEDS D19 and D21 stay lit. D20 does not light or blink. I'm not sure if it flashes right when it's turned on, I'd have to check again.
Driver Board LED 2 is OFF and the manual says it should be on.
All other LEDS appear correct, even the DMD Board light.

I read that the Varistor might be the problem with the circuit breaker issue, so I took a look inside, and it had no Varistor or Thermistor. I could see where a Varistor had been in place before, but had been cut off. I ordered and installed a Varistor. The machine still resets my house breaker 50% of the time. I did not see where a thermistor had been in place, so I did not install one.

I've tried just booting with just the power plugs to the CPU and Driver boards only (nothing else attached). I just get the same LEDs as above, but cannot see the DMD garbled lights since the DMD board is disconnected.

I thought the CPU board might be to blame since it had failed and been repaired a few years ago. I ordered a Rottendog modern replacement. Installed it, and the LEDs exibit the same behaviour as the original board. I switched back to the old board to verify.

I just pulled the driver board for the first time since I've owned it. Now I didn't see anything obviously damaged, but I did see quite a few spots where repair work was performed by someone named "Zero".

Would a driver board cause the CPU to not boot (D19 should turn off and D20 should flash)?

I don't know what to do next. Since I have the driver board out, I think I'll take pictures. Are there other things I missed, and should check? I've gone over the underside looking for something shorting, or broken during the move. Nothing seems out of place.

Thanks for reading and any help,

Pat S

I have. At this point I've taken off every electrical connection in the backbox at least once.

Thanks for helping me

Yes, my sound board looks similar to the pictures you linked, but a little worse.

I just carefully looked at the cables. The 26 pin has the slightest score marks on it, but it does not appear to have burnt through any of the wires. I'm happy to replace it, but I'd like to test it first.

I've tried booting without the cables. No difference. I will try again once I've put the driver board back just to be sure.

Thanks!

Ok, put it back together today. The only new bit of info was that when the DMD ribbon cables are disconnected from the CPU, the CPU D20 LED flashes.

Ribbon on.
D19 Stays Lit
D20 Stays off
D21 Stays Lit

Ribbon off.
D19 Stays Lit
D20 Flashes
D21 Stays Lit

Yes. The soundboard is removed because it fried. I will try to learn how to check the 5v section.

I actually purchased a Pinsound, but have not installed it because the machine still has problems.

Thank you!

I think it's GF type (late 1970's house). It does have the ground lug. Regarding that issue. I did install a Thermistor today, and that has reduced the amount of times it sets off the breaker, but it still happens.

Does anyone happen to know what causes LED 2 on the Driver board to stay off? High voltage problem?

When it did flash, it was random, like watching morse code.

I think I should probably have them all tested after a little more troubleshooting.

Thanks.

I've measured the test points. I'm trying to learn how to check the plug. If you mean how much voltage is at the wall outlet, it's 122v. If you mean at the circuit breaker, I'd have to learn to check first.

Test results

TP1 18.4V
TP2 4.8V
TP3 12.1V
TP6 88V
TP7 26.7V
TP8 22v

Are these wires ok? I'm in the US. They appear offset a row compared to the picture in the link above.

IMG_20180306_035219828 (resized).jpg

IMG_20180306_035319494_HDR (resized).jpg

Well first of all, thanks for helping find this!

If this is the problem, I'm really confused at how this came to be. I'm scared to repin it because, how did it work at the old house this way? I'm trying to think if anyone else might have touched this.

I hope this got it. If not, just let me know, I have no problem trying again.

Thanks zaza!!!

IMG_20180306_061731611_HDR (resized).jpg

IMG_20180306_061721844_HDR (resized).jpg

IMG_20180306_061837334_HDR (resized).jpg

IMG_20180306_061851613_HDR (resized).jpg

IMG_20180306_061910378_HDR (resized).jpg

IMG_20180306_061935550_HDR (resized).jpg

I'm going to wait to hear back before trying anything, but just to let you know, I cannot figure out how to remove the pins...

Thanks all.

Well, it took a while to get those pins out without damaging them. My back is telling me to lay down now

I turned it on, not knowing what to expect, and at first glance, the only thing different is that LED2 on the driverboard is now lit. Which is great. I'll test voltages again in a few minutes. The CPU is still stuck with D19 and D21 lit. The DMD is still showing non moving snowy image.

Thanks again. That's progress at least.

TP1 was 18.4V now 15.8
TP2 was 4.8V now 4.8
TP3 was 12.1V now 12.1
TP6 was 88V now 75.8
TP7 was 26.7V now 22.4
TP8 was 22v now 18.6

Leds on the board 124567 are lit.

Now, are my CPU chips in the right way?

IMG_20180306_073543672[1] (resized).jpg

I reseated the 3 connectors, and tried again. Same scenario. D19 stays lit. D20 flashes for an instant then stays off. D21 stays lit.

I can try reseating the chips. I also have a rottendog CPU board I can try.

Does this indicate something needs to be rebuilt in the driver board to get to 5v on TP2?

I will look into these steps.

Thanks to each of you for the help.

Update on this T2 Pin. I sent my driver board in to get repaired. I also ordered a new rottenddog driver board which I istalled it tonight. TP2 now gets 5.1 volts (instead of the original board with 4.8), but the CPU still does not boot. D19 lit, D20 off, D21 lit.

I again swapped the CPU chips over to a new rottendog MPU board, and I have the same results.

I'm thinking now that I should I buy new CPU chips? I've tried booting with the data cables off, and the cabinet stuff disconnected, just power to the driver board and CPU, always the same result.

I'm happy to try any suggestions here. I can take pictures and videos if that will help.

I'm in Spokane Washington btw. Does anyone know anyone nearby that an help?

Thank you for any assistance.

Would this be a suitable replacement...?

ebay.com link: MC68B09EP Microprocessor DIP40 Replacement of HD68B09EP MC68B09EP

Thank you!

Oh that's great. I'll see if I can do that. Thanks again.

I swapped over the 68B09EP from the sound board to the CPU board, and same result.

My next thoughts are to buy a new chip located at U6 (not sure of the name), and then ASIC. Open to any suggestions.

D20 always lights for the briefest period when the game is switched on then goes off.

I'll make a video of it.

I ordered a U6 chip. If this isn't it, I'm going to try and get someone to look at it or send the boards to be inspected. I'll update after the chip gets here.

Thanks all.

The rottendog cpu board did not have the ASIC, U4, or U6. I transferred those from my old original board. I have a new game rom on the way as well as a new ASIC now. Looks like they will arrive around the 20th. I will not install any of these without being sure of the orientation. If I'm not sure I'll post a picture here.