I would check everything in the 'Ball lifter motor' circuits.
1. Manual lift button...... closed ?
2. Timer stepper unit..... verify it moves smoothly by manually stepping/ reseting it.
@ should reset to Zero position , then step up one rivet ( position 1).
3. Extra Ball unit........... same as above.
ScreenHunter_165 Aug. 11 18.21 (resized).jpg

One of these units in the picture. There should be a label near the unit to identify it.
Verify the unit moves freely when you Step & Reset it manually.
*** I mentioned this in a previous Post...

ScreenHunter_166 Aug. 12 09.30 (resized).jpg

Bally Bingos also had a 'knock-off' switch under the cabinet so the store owner could reset the
Replay Counter to payoff Winners when the player wanted to 'Cash out'.
Are you sure the switch in question is not a 'Knock-off' switch.
The manual Ball Lift button has a purpose.

I am labeling things as I learn their physical location. I've learned to find things on the schematic and in the manual. Sometime I feel like a nut, sometime I don't.
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You have to have a 'Good sense of humor' when you work on these Bingos.
A large bottle of aspirin also helps!
We are lucky to have nick here helping us.......all the others must be on Vacation still.

That will be Fun..........
There are only a few circuits for ball lifting; I would try to isolate the problem first before doing that.
****** Edit...... I would wire in that manual Ball Lift switch first, if I was T/S this, but that's me.
Just my thoughts.
ScreenHunter_171 Aug. 20 10.33 (resized).jpg

JKnPA - I have been studying the schematic. The added manual ball lift button wired to the eighth ball switch in the trough has me wondering if I should take it out and focus on fixing/restoring the original manual lift button under the shooter. When the eighth ball rolls into the trough, the ball lifter lifts one ball. If I push the added button, another ball is lifted.
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Sometimes We buy Bingos that are ALTERED.......... always a problem.
I have a 'BeachTime now, that has extra wires on my C.U. 16 switch...... who knows why it was added!
I would try to keep the Bingo wired according to the manual. Just my Opinion.
**** Note : Your Timer Unit should step to pos.2 when you shoot your first ball.
Maybe your Timer isn't stepping Up. I would look at that particular circuit.

the timer unit is almost always one of the steppers on the bottom of the back door. Usually it's the middle unit (just right of the reflex unit) ... which it is on laguna. JKnPA has the right idea in post #6, but he didn't notice the pic is the score units in the middle of the door instead of the stuff along the bottom.
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You are correct Sir.
I thought that was the bottom of the door area.
I was hoping there were labels still on the door so he could locate the Timer.
The Timer is usually a major source of Problems.
***** We always appreciate your help *****
Best wishes,
John