Williams Aztec (Williams, 1976) problem w/Special

[njPinWiz]

Williams Aztec problem: Out lanes scoring & advancing bonus properly during regular play. But, when A-Z-T-E-C is spelled out and 50,000 bonus is achieved the Special light comes on one of the out lane alternatively. Ball rolling over Special lit lane does not give credit/knock/score points. Seems like the machine is not recognizing when Special is achieved.
Any ideas? Thanks

 

[njPinWiz]

I forgot to mention that the bonus stepper unit keeps trying to advance even when it is maxed out at 50,000. Something is not switching over to credit/knocker when special is lit.

 

[pinballdaveh]

First the easy question. Once the bonus unit reaches it’s max of 50,000 the gear has a gear tooth removed, so the bonus unit advance coil can’t advance the gear any further.
Troubleshooting the special problem.
As you know when you achieve max bonus and have lit all the Aztec letters the special lites will come on and alternate in the outlanes.
When these conditions are met the set up relay pulls in and stays pulled in. This is working correctly. The problem is in the circuit path from the rollovers to the credit unit step up coil.
The relays and switches to check are.
Set up relay
N.O. Switch with grey-br & blu-w wires, 2nd switch from relay frame.
N.C. Switch with b-g & b-w wires, 4th switch from relay frame.
Bonus relay
N.C. Switch with blu-w & grey-b wires, top switch from relay frame.
Change relay
Make-break switch with g-o , r-o , & b-w wires, 2nd switch from relay frame.
Make-break switch with g-o , r-o , & b-g wires, 3rd switch from relay frame.
Bonus unit
This circuit also goes thru the wiping finger disc.
The wires involved are g-o bottom of the disc connection #1 and grey-b connection #3. These 2 connections can be jumpered to possibly help with the troubleshooting.
Also when a outlane special is awarded you don’t get the points score also. It’s one or the other.

 

[njPinWiz]

thanks pinballdaveh...I am on the right track. checking/cleaning those exact switches on that relay. will report back later.