I have recently upgraded my AFM to NVRAM (my first WPC-95 NVRAM upgrade). I have upgraded several other WPC and WPC-S games before to NVRAM without any problems.When I ve installed NVRAM I did not notice that the game had the 62256 SRAM so I did not make the necessary changes to the CPU board to host a 6264 RAM (or in this case a FM1608-120-PG). After booting the game it did not boot correctly. I have performed the necessary jumper and resistor changes but the result remained the same (I have also put a 6264 RAM, but the symptoms remain the same).
When I power the game on it loops in the sequence:
On startup
1) led 201 and led 202 are lit (for appropriately 4 seconds)
2) led 202 is on, led 201 goes off, led 203 starts blinking (quickly about 5 times) and repeats this cycle a few times
3) I get two bongs while led 601 blinks 2 times
occasionally strobe lamp starts for a second and saucer shake coil fires.
The other sequence goes like this:
1) leds 201 and 202 are lit
2) led 3 blinks slowly 2 times
3) I get two bongs while led 601 blinks 2 times
I have verified continuity of the traces below NVRAM sockets and everything seems to be ok. I have also replaced S2 audio eprom on the sound board and I still get two bongs. If I put in another CPU board the game works ok.
I am out of ideas myself and would really appreciate some suggestions to help me successfully repair the CPU board.