Floundering Fishy

[Alan Syson]

Had problems recently with FT resetting. Wasn't like a "normal" 5v reset ie lots of flipper or multiball action, it would happen at any point in the game.
Went to check voltages and while doing so the DMD went off and there was a loud buzzing, (see video) also D19 on the CPU remains on.
Pulled the driver board out of another machine, same results.
All clues, guidance and pointers welcomes,
Cheers, Alan.
View attachment IMG_1593.mov

 

[drhex]

Reseat all the ribbon cable connectors. Disconnect the soundboard and see if that makes a difference. Nothing on the DMD at all? D19 is blanking which will keep solenoids from firing. Can you try another CPU?

 

[David_Vi]

Mine did this too, coincidentally a fishy. I'd tried reseating everything, and put a 5v reset board thing in it as it was at the pinball office so needed to survive, but it would still reset randomly.

Eventually changed the voltage regulator and it hasn't done it since .
I got one of those modern versions that you can adjust using a trim pot.

 

[Alan Syson]

Reseat all the ribbon cable connectors. Disconnect the soundboard and see if that makes a difference. Nothing on the DMD at all? D19 is blanking which will keep solenoids from firing. Can you try another CPU?

Reseated cables and disconnected sound board, no different apart from no buzzing noise. DMD blank, D19 and D21 permanently on, D20 flashing.
I could put the CPU from Flintstones in but I don’t have an asics puller, would this matter if I only wanted to use it for diagnostic purposes?

 

[Alan Syson]

Mine did this too, coincidentally a fishy. I'd tried reseating everything, and put a 5v reset board thing in it as it was at the pinball office so needed to survive, but it would still reset randomly.

Eventually changed the voltage regulator and it hasn't done it since .
I got one of those modern versions that you can adjust using a trim pot.

My initial thoughts were 5v problem.
Initial thoughts were clean up j101 then check voltages. Started with 20v TP7 and the buzzing started with no DMD. If I shorted TP7 to the ground TP, I’m certain I didn’t, would that knacker in the DMD and sound?

 

[drhex]

Flintstones is a WPC-S, that isn‘t compatible unfortunately. Does disconnecting the flat cable to the PDB make a difference? If you short TP7 to ground F111 will go. If you short TP7 to 5V all kinds of hilarity will ensue. What test equipment do you have? You do get a bong, no buzz with the flat cable off the sound board? Blanking comes from the ASIC, is that secure? Press it in if you havent done that yet.