Hi uncle_jose
when Your pin does collect single bonus: Does the stepping down the bonus-ladder is MUCH faster then "stepping down the bonus-ladder double bonus / triple bonus" ? It MUST.

See the JPG --- Single Bonus means the "AA and DD Switches" are "as shown in the schematics - as the Double-Bonus-Relay is not pulling. FAST stepping down on the Impulse-Wheel-Switch-Stack beeing pulsed five times per turn.

IF (if) the stepping on single bonus is fast: Then the "AA-BB" stuff works --- You must investigate in "DD through EE to Switch on Ball-Index-Relay" --- switches clean ? wires soldered-on ?

IF (if) the stepping on single bonus is "slow as on double / triple bonus": You must consider also the "DD etc" - BUT first investigate on the "AA through BB to Bonus-Reset-Relay". Greetings Rolf

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Hi uncle_jose
we can lift the playfield - 15 degrees, 30, 45, 60 degrees and use the wooden stick or metal stick to hold the playfield in this position.
We can lift further 75, 90, 115 degrees - pull the playfield a bit against the player and lean-on the playfield onto the Backbox. Not very stable - may want to secure it. Maybe a bit better access to "relays mounted on a relay-bank" ?

The FIRST thing I do when I look for a fault: I toggle-off the pin and unplug the main power cord (Safety Reasons). From schematics and manual I take the information "Switch-XYZ on Relay-QQ" and the color of the involved wires are "whatever-one" and "whatever-two".
I locate in the pin the relay and the switch --- I grab the wire in question and gently pull a bit - question: Soldered-on or broken-off ?

Maybe one of the involved stuff sits in the Backbox and another goody is mounted on the Mech. Panel in the Cabinet: I also check the Jones-Plugs (wires soldered-on or broken-off ?).

I dislike to work on "Switches in Relays sitting in a Relay-Bank" --- I dislike to work on "Switches on the Score-Motor". So sometimes I am rude to the pin --- I cut a wire a couple of inches away from the Solder-Lug. I take a cigarette-lighter and burn away the insulation fabric. Now I have a place to mount an Jumper-Wire for testing. See the JPG - "red line jumpering testing the single-bonus feature".
When the Single-Bonus-Feature works: Fault must be in "what I have jumpered".
When the Single-Bonus-Feature still does not work: Fault must be in Score-Motor-Switch or other connecting wires.

K-Mart and such stores - automotive departement - car-electrics --- they sell single male and female plugs - we can attach the wire by squeezing the housing of the plug --- very practical.
And when I have finished testing: I plug together the cut wire and have these K-Mart-plugs in my pin forever ... Greetings Rolf

Hi uncle_jose
and here is the JPG, greetings Rolf

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