Hi all, I need some help!! I was having some intermittent problems with one of my switches on my TZ so I changed it out. When I turned the game back on I got the "check fuses F115 and F116, J112 and opto 12v supply" message. Everything was working just before I changed the switch. If I go into test mode all switches work (including my new switch) except the opto switches. The clock works as well.

Here are my observations so far:

checked fuses f115 and 116, both are good.
reseated J112, no change
reseated ribbon cable to MPU, no change
tp1 is 13.9vdc
tp2 is 5vdc
tp3 is 12vdc
I've got +13.9v on pin 2 of J116,117 and 118
I've also got +13.9v on the opto board in all 3 locations (took me a while but I managed to verify this). The LED on the opto board is lit.
LED7 on the driver board is lit.
LED3 kindof pulses irregularly on and off on the driver board. I'm not sure if that is normal.
infrared leds are working (verified this with a camera)
all opto switches are NOT working

I'm kindof at a loss now. I have a driver board in my WH2O I could swap in but thought I'd check with you guys first to see if there is anything that I've missed. I'm not sure what would cause all optos to suddenly stop working.

hmm.. I've read the guide at pinwiki but I haven't seen Clay's guide at all. My fuses are good and it looks like I haven't lost 12v at all so I don't really suspect a power problem.

Will give that a shot tonight and report back.

Just to clarify... only the optos on the 10 opto board under the playfield are affected. All other optos/switches are working (clock optos are working, so are the flipper optos).

Thanks for the link.. very interesting read. Following that thread I've got to the point where I'm pretty comfortable that I'm getting the proper voltage to the opto board because I've checked everything they have suggested. That and the IRs themselves are ON and are visible with a digital camera.

My next plan of action (after re-seating the ribbon cable) will be to unplug the switch matrix from the MPU and attempt to fire the switches with a jumper. If that is successful it must be the opto board itself.

This is the procedure I'm referring to: http://pinwiki.com/wiki/index.php?title=Williams_WPC#Switch_Matrix_Problems

I socketed and replaced all LM339s on the opto board... I'm back in business. Thanks for the help!

By the way, I didn't actually end up having to test the switch matrix to determine there was nothing wrong with the MPU. Because switches were registering in the same rows and columns as the opto switches I knew there was nothing wrong with the switch matrix. I also was getting +12v everywhere I should so it was definitely the opto board. Total cost of repair was ~$3 (3 ICs and 3 sockets).

Yeah no kidding! I'm still at a loss as to how exactly I blew them in the first place cause I only worked on the machine with the power off. In any case I've found that a lot of people have had a similar experience with them as me. I also bought a few replacements to have in stock in case

I'd have to check on my W?D but I believe the opto board will be under the playfield. That is where it is on TZ at least.

Yes fix this right away. If those wires touch for whatever reason you may have bigger problems on your hands. I personally know someone who purchased a game with a similar hack fix and it fried his transformer!!!

+1

I've ordered a lot from these guys!

I was always getting ~13V at the opto board. Everything else looks pretty good.