It's slightly confusing when you say that the AX relay is trying to "reset" since there is an AX relay and an AXR relay. The AXR relay is the AX Reset relay. See what I mean?

Do you mean that AX is pulling in when the score motor runs?
If so, the fact that AX is pulling in runs the score motor. That relationship is normal.

It would seem that the problem is that the AX relay is pulling in. Examine your schematics. Find the AX relay coil. What switch closure conditions must exist for the AX relay to pull in?
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Chris Hibler - CARGPB #31
http://www.Team-EM.com
http://webpages.charter.net/chibler/Pinball/index.htm
http://www.PinWiki.com - The Place to go for Pinball Repair Info

6.8.1.1 Gottlieb® Score Motor will Not Stop Running: Frequent Cause
Here >> http://pinwiki.com/wiki/index.php?title=EM_Repair#Gottlieb.C2.AE_Score_Motor_will_Not_Stop_Running:_Frequent_Cause <<

6.8.5 General: Score Motor Keeps Running << Read this part too just below that ^^
The bonus unit zero position switch?

Be careful with those "x" set-reset relays (AX etc). The travel on them isn't very much and they must be set correctly to work.

I recommend reading both the Pinwiki em sections and Pinrepair completely just to get an overall understanding of how all parts interact. Sometimes what may seem like one thing turns out to be something else completely! I have tracked down many gremlins and often that's the case.

These are the items which will cause the score motor to rotate.

D: 500 Point & Add Bonus Relay
E: Bonus Unit Score Relay
G: Hole Relay
Q: Game Over Relay
P: Add Player Unit Relay
S: Start Relay
W: 2nd Chute Relay
AX: Reset Control Relay
Motor 1C: Score motor Home switch

Here is a pic of my Spirit of 76 board. I suspect it may be similar to your Pioneer.

Relay_Board.jpg

I'd suggest starting your machine and let the score motor run as it does, then locate which of these relay(s) are energized.

The score motor home switch is #1C. In my photo, it is the switch stack which is in the 6 o'clock position, the one which rides on the top disc cam itself. I am assuming the Pioneer will be the same but I am not sure of the motor switch assignments.

Nice detail, Steve. That board looks soooooooo clean!

You do good work.

Thank you for the compliment Prmailers.

Here's a photo of the original score motor:

ScoreMotor.JPG

The original thread of my SO76 is here: http://pinside.com/pinball/forum/topic/first-em-pin-in-30-years

Just checked out your other thread.

What a steal at $150!

Great work.