Set up the 2nd Williams Flash this evening and got started on it.
Reflowed all of the connector pins, cleaned the connectors, and pulled all socketed chips and cleaned their legs on all boards in the back box and the sound board in the lower cabinet. Fuses were all pulled buffed up and reinstalled. All fuses tested good.
Replaced the 5101 with NVram right away and removed the existing battery holder. Zero acid damage on this MPU. Awesome.
Powered up the game and the left kicker (special solonoid #5, (21 in test) is locked on. I removed the wire from the driver board connector (2J12, pin 8 if I remember correctly) temporarily to test the rest of the game. came up in diagnostics right away. Set coin option setting 18 to 00 for free play and powered off and back on and we are in attract mode.
There are zero feature lamps that work, but all of the GI is lit.
Went into test mode and the displays are perfect.
All coils fire except for the right kicker. And we have sounds as well. Need to turn background sound setting on in diagnostics to test that.
Most switches seem to be working well, but the drop targets need to get a good cleaning. Time to take them apart and clean them up a bit.
Issue to resolve:
-clean up drop targets
-no feature lights in back box or playfield
-locked on coil
For the locked on coil, I swapped out driver boards with a known working one from my Firepower and it works fine so issue is narrowed down to that specific driver board. Replaced the associated pre-driver and driver transistor and it's still locked on, time to move up the chain to the 7408 or PIA after a bit of poking around with the probe. One of the resistors for that coil on the driver board is just a bit out of spec as well. Going to replace that too and see what happens. I think I might have a test chip for the Williams system 3-6 boards here. I don't have a test LED, but I do have a probe.
What pins do I need to be looking at on the 7408 and PIA for that special solenoid to see whos locked on, or should I just socket and replace both of them with a new driver/pre-driver all at once and that should be the whole chain.......
The intermittent drop target issues I expect to be resolved after a good cleaning of all the contacts and boards with some possible adjustments of switches to be made.
Any ideas on why all of the controled lamps would be out? All of my fuses are good. I've double checked them out of the fuse holders. Going to do some voltage testing to see if there is a break down somewhere.