Hi Barry
if the stepping ONLY does not work when a new ball is kicked over to the shooter alley: See the JPG. Greetings Rolf

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Hi Barry
I do not remember the Grand Prix good enough - by now I only can look at the schematics. The snippet I show: The Bonus-Unit steps up after starting a new game - resetting the Score-Drums - eventually resetting the Bonus-Units --- kicking out the very first ball: NOW stepping up on both Bonus-Units. You play and play and every time You loose a ball: Some bonus is collected - playfield stuff is resetted - new ball is kicked over to the Shooter Alley - NOW stepping up on both Bonus-Units.

From memory and descriptions I believe You can have the ball rolled into a Eject-Hole on the playfield - bonus is collected and the ball is kicked-out out of the playfield-Eject-Hole - NOW this Bonus-Unit is stepped up.

Of course when playing a ball You can step up - play - step up - play - play - step up.

New question: Does this UNIT ever step-up ? (((If "No": Maybe the coil is dead ?))) Greetings Rolf

Hi Barry
good - the ipdb has the schematic and the manual --- there on page-12 (ori-10) I learn: The Right Advance relay is mounted on the playfield, the Right Eject-Switch is part of the Right Eject-Hole - therefore is mounted on the playfield, the Right Bonus Unit is mounted on the playfield.
BUT the Score-Motor sits on the Mech-Panel in the Cabinet - there must be a wire from the Mech-Panel of color-B-W-3 means Black-White but this color is also used on non-related other places - anyway: The manual on page-14 (ori-12) shows an Size "22" Jones-Plug in the connection Mech-Panel to Playfield --- see in position-6 the mentioned wire-color-B-W-3 --- all good with this Jones-Plug ?

If You do not find an error there - we then must investigate in the Score-Motor-cam named "3" we see in the schematics --- Bottom-most switch in the stack is SCM-3-A. Greetings Rolf

P.S.: My JPG shows: Maybe the wire coming from SCM-3A then is connected to "A" or maybe to "B" or maybe to "C" --- so have a look at "Right Advance-Relay (wires soldered-on ?) - have a look at the Right Eject-Hole-Switch (wires soldered-on ?) - have a look at Right Bonus-Step-up-Coil (wires soldered-on ?) Greetings Rolf

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