I've got a Xenon that I'm trying to get to boot. When I turn the game on, a few play field lights come on, there is speaker buzz, and the LED on the MPU goes solid dim.
I took the MPU out and fed it +5VDC, +12VDC and GND through a computer power supply and (after replacing the 5101) got the 6 flashes I'm looking for.
Per "the guide," I put the board back in the game, I disconnected all the connectors except J4, the power connector.
At this point I measured the +5VDC and + 12VDC test points and got an odd reading of +4.1VDC and +11.1VDC respectively.
Also per "the guide" as long as your power supply is good, with everything else disconnected, a known good MPU should boot.
Admittingly, I got a little lazy (the power supply boards are very servicable) and I found a good discount on a new Rottendog power supply.
Threw the new power supply in, same result. +4.1VDC on the +5VDC test point and +11.1VDC on the +12VDC test point.
Here is what I don't understand. Per "the guide," you only need the power supply hooked up and J4 on the MPU plugged in to test this board in the game. However, there is no +5VDC coming from the power supply, apparently +12VDC goes to "J3 pin 10 +5 regulator input" and J4 on the MPU is the power connector but it's expecting +5VDC.
Also, with all MPU connectors plugged in, same symptom, a few lights, speaker buzz and a solid dim MPU LED.
Just for good measure, I already have this coming:
Any ideas? What's the simplest way to get +5VDC and +12VDC to the MPU so I can start working from there? Is just having J4 plugged in the MPU sufficient? Is my problem really on the solenoid driver board?