Firepower 2 balls

[philtech]

Hi Everyone...

 I have my firepower 2 somewhat up and running, and its been a painful experience.!
I gave up repairing the MPU and driver board as they seemed to far gone, so bought a new "MPU driver combo board" and power supply board from Mad Amusements.
Everything came to life, and going through the test sequences I had to fix a few switches.

 The machine plays perfectly until a ball is shot into the eject hole.
When a ball drops in the eject hole, a new ball is instantly put in the ball shooter trough.
Everything plays great until this second ball goes into the outhole, and thats where everything stops with no more balls provided.
Sounds keep playing and all lights working but no new ball is put in the shooter trough.

 Ok, if I reset the machine,, the ball stuck in the eject hole gets shot out, and once it drops into the outhole a new game can be played.
I have checked over and over all switches and now I am stumped.

Any ideas on what's wrong would be greatly appreciated.

Thanks.  Phil....

[Strangeways]

I've not seen the Rottendog MPU board - but is it setup (dipswitches) for the right game ?

Check the switches are working in the trough. There should be a switch test.

[MartyJ]

Phil,

In addition to what Nino has suggested, if in fact the board is a Rottendog one, have a very close look at how the board is mounted.  From memory where the switch row inputs sit on the PCB (2J3) rests very very very close to the mounting bracket.  Just make sure its not touching and shorting out the row.

[philtech]

 Yes the MPU switches are set for the correct game, and all switches in the trough (and all over the play field) work perfectly performing a test sequence, plus I have checked every switch with a multimeter numerous times when the game freezes. I have also tested every diode.
Its a weird thing because the game works 100% unless a ball drops in the eject hole. Trust me the switch there is perfect as I have had a meter hanging off this.  For some reason after a new ball is provided, it seems like the MPU forgets the ball in the eject hole is there,,, if that makes sense.
Thanks....

[philtech]

Phil,

In addition to what Nino has suggested, if in fact the board is a Rottendog one, have a very close look at how the board is mounted.  From memory where the switch row inputs sit on the PCB (2J3) rests very very very close to the mounting bracket.  Just make sure its not touching and shorting out the row.

Thankyou, I will check this in the morning.
I did remove the bracket that was used to hold the MPU board as was stated in the Rottendog instructions, but you have me thinking I should check all other areas as well.
Regards Phil...

[philtech]

 Ooooops, I found the culprit and its ME.!
The instruction manual says to insert 3 balls, but this obviously is not correct.
I took one ball out and the game runs perfectly.

 When the game froze, I found that if I switched off the "right ball ramp switch" a new ball would be ejected.
This got me thinking this switch needed to be turned off so the program knows there are 2 balls on the play field.
But with 3 balls inserted this switch is constantly turned on which confused the game sequence.

 I can not believe I wasted so much time not seeing the obvious.
But I am a little confused, although happy now, as I thought most Williams machines were designed for 3 balls.

[goodolddays]

Glad to hear you sorted it out . I hadn't heard of a game with only 2 balls before.
I too have wasted a lot of time not so long ago chasing a fault and overlooking the obvious.