Hello friends.

Here I have a problem of G.I playfield on my arabian. The 3 complete lines does not work.
The Backbox and the door light work well.

Th connectors J103 - J104 -J105 -J106 were redone before the failure.
I have the version of the drivers already corrected (without the diodes). I changed the J102 Driver-CPU interconnection cable.

The fuses and fuse holders are OK. The transformer output voltages are good. The voltages on the J103 connectors are also good.
I put new Triacs BT138-600. When I short-circuit the legs of the triacs, my lines light up well. I reset the game, remove and reset .... Still nothing.

In attrack mode my triacs do not heat up, they are cold. So I think it is not ordered.

I changed on Driver U2 74LS374 and U1 LM339. Always nothing.

If I disconnect my GI tray connector and I measure the voltages on the direct connector on the drivers I have about 7 VAC. By cons as soon as I connect the connector the voltage drops to 2.85 VAC.

Here are two nights that I am blocked above. Thanks for your help.

Hello. Thanks for you reply .I did this delicately. Nothing better

Hi pinmike. Thanks for welcome.
I Reflow fresh solder on CPU and Driver. Always nothing.

I do not know what to do !!

Ok. In Zero cross test pin i have 1.1 vac and a approximately 109 Hz with my multimeter. thanks you dude

HI friends . I fix my G.I problem.
CPU was bad

Change U12 74ls240 ans, U1 74L244, and U3.

Thanks Pinmike ans Ronkz650 for help.