Williams Police Force (Williams, 1989) won't boot

[wbox]

Hi Guys,

Pinball doesn t boot. No fuses or big transistors are blown.
PSU seems fine, the +5V does lit up but not the other 2 status leds.
3x1.5V voltage seems fine....

Nothing is displayed on the front and strange sounds are emitted when powering on. Sometimes continous beeps, sometimes nothing....

ideas?

Thanks,

Vincent

 

[spalmer]

Disconnect all connectors from the MPU board except 1j17. Check for +/- 12 volt. if 12 volt is missing it will not but. It could also be another board that is causing the issue. If it tries to boot with just 1j17 connected, start plugging in boards one by one until you find the one keeping it from booting. If all else fails, I have a system 11a F-14 Tomcat that I can diagnose your board in if you want to ship it to me. I can provide a reference. With the strange sound issues you are describing, I am thinking that your sound board is causing your problems.

 

[wbox]

Thanks! I ll try that asap.