Grand Prix
Williams, 1976I've been working hard to get this machine to work but now I'm having an issue when any time the bonus is advanced on the left side it immediately counts it down and adds it to my score. Super annoying and not sure where to start. hope its something obvious. Any pointers would be great. Thanks in advance.
If a set of switches in the Left Bonus Relay are closed when they're suppose to be open,
the next time the Score Motor energized, this would happen. I'm thinking maybe a set
of switches in the Left Bonus Relay..
Mopar the thing is, I dropped down my left bonus stepper unit to work on the flippers and after I put everything back together I noticed this issue. The Left Bonus Relay looks fine and according to the manual I have the switches adjusted correctly. I also noticed that when the game starts and ejects the ball the left bonus stepper unit doesn't advance by 1 to light the 5000 light on the playfield. I'm assuming this is because something is stuck telling it to count down. Wish I had a picture of a working left bonus unit stepper to compare mine. For the time being I adjusted the switches to match the right bonus unit. hopefully someone can point me in the right direction.
just poked around a little more and the advance left bonus stand up switch is acting as if its the outhole switch. anytime I press the switch the ball count unit advances to ball 2, 3 etc. still not sure what's goin on. going to have a look at the schematics and see if anything stands out. Right bonus is working correctly.
Inspect each stepper unit that includes a brown bakelite plate with riveted contact points.
These plates can be rotated clockwise or counter when the screws are loosened.
Check that they all line up and are not slightly skewed.
After adjustment notice Spider contacts / rivets.
ok so I found that the paper on the switch in the outhole was missing causing the machine to think the ball was constantly in the outhole which explains the bonus unit counting down. But, now the problem I'm having is the left bonus unit isn't advancing after completing the spinner sequence. The spinner adds points but doesn't advance the left bonus.
Quoted from dgamboa1988:The spinner adds points but doesn't advance the left bonus.
So I take it the Spinner lights are working okay which means the left Spinner Relay is working.
There a set of switches in the Left Spinner Relay, and the circuit also goes through the Left Spinner's
Unit disc. There must be a double disc. One for the amber lights, and one to pulse the Left Advance Relay.
ok so I found a loose wire going to switch 1a on the spinner relay stack. soldered it back in place and now my right spinner/ advance is working. New problem popped up of course. Now I have an issue when I drain the ball the right bonus unit counts down but the ball count relay doesn't advance after counting down or pulse the bonus unit after its done like its supposed to. would this be switch 3a on the score motor causing this? Mopar
phil-lee
Quoted from dgamboa1988:the right bonus unit counts down but the ball count relay doesn't advance after counting down or pulse the bonus unit after its done like its supposed to
If the Outhole relay doesn't activate when this happens, Inspect and diagnose this circuit with Alligator clip jumper wires
http://www.planetimming.com/Pinball/troubleshooting/EM%20Troubleshooting.pdf
http://www.pinrepair.com/em/index3.htm#features
Example of a pinsider actually doing this https://pinside.com/pinball/forum/topic/red-baron-tech-question#post-5858156
pasted_image (resized).png Okay, and also the right Bonus counts down fully, but doesn't step up one. Correct?
If the Left is doing the same thing, I'd inspect the make/breaks in the Outhole Relay.
If the Left Bonus is working properly, then I'd check the score motor's C 3a set of
switches. That's the 5th cam from the left, bottom set of switches
The way the score motor cams are shown on the schematics is a little goofy.
Unless you look at it upside down, the right cam (the impulse cam with 2 sets of
teeth, 5 teeth per set) is on the left, and the Index cam (the cam with the run-out
switches) is shown on the far right. But anyways, the set of switches that step up
the Right Bonus is known as 3a, which is actually the center cam. 5th from the left,
and 5th from the right..
made the mistake of saying right relay in my last post, but the left relay is actually the problem. You do have it correct though, it counts all the way down but doesn't end the ball and move to ball 2. anyway, it seems like the alternating relay isn't pulling in at the end of the ball which doesn't step up the ball count unit. when I push in the alternating relay manually when I hit the out hole switch the game moves to ball 2, 3 etc. 
HowardHurtz Mopar
SOLVED!!! using alligator clips I figured out that a zero switch on the left bonus unit wasn't making contact even though it looked like it was. I also went through and adjusted all the switches on the score motor. Now my game is working 100% for all 4 players! couldn't have done it without the help from Mopar and
HowardR
Quoted from dgamboa1988:SOLVED!!!
Good to hear! I was just about to let you know the bottom set of switches on the 3rd cam from
the left activates the Bonus Step Up when the Outhole Relay is energized, but the funny thing is, there's
no other break on the schematic except that score motor switch and the make/break on the Outhole Relay,
meaning as soon as the Outhole Relay is energized, that score motor switch would want to energize
the Bonus Step Up. I didn't check it on my machine yet, but I figured there had to of been another
set of switches in that circuitry that made once the Bonus Unit reached its reset position. With those
schematics, no wonder they claim Grand Prix can be a rough one to shop out. (haha)..
Anyways, good to hear all is well. There's quite a few that like that machine..
Okay, so Players 2 and 4 10,000 points score, but not when 9,000 flips to what should be 10,000.
So if the second and fourth Player's 1,000's Score Reels' 9th position switches seem to be making good
contact (of course when on the 9th digit), then I'd inspect the Player Step Up Unit. Check the wires,
solder tabs, and make sure the wiper has the proper amount of tension on its wiper board.
I know, it's working on Players 1 and 3, but I've seen it where it still needed a little more tension.
Also check that the wiper is aligned squarely on the wiper board rivets. If all seems to be okay,
it could possibly be on the backside of the wiper board, but not as likely..
btw: I believe it's a bladed wiper. Not a snowshoe (individual spring loaded)..
Quoted from dgamboa1988:10,000 point relay isn't pulling in after my 1,000 point relay rolls over.
As Mopar suggested, if scoring 9,000 + 1,000 doesn't activate the 10,000 Point relay on player 2,
Starting with the indicated contacts on the Player Unit disc, Inspect and diagnose this circuit with Alligator clip jumper wires
http://www.planetimming.com/Pinball/troubleshooting/EM%20Troubleshooting.pdf
http://www.pinrepair.com/em/index3.htm#features
Example of a pinsider actually doing this https://pinside.com/pinball/forum/topic/red-baron-tech-question#post-5858156
SOLVED!!! This time, its for real! After using alligator clips from the 9 position switch on the second player 1,000 drum to the 10,000 point relay all players are now back to scoring correctly. not sure where the short is, but at least I know the r/o wire is broken somewhere. Thanks again for your guys help! HowardR
Mopar
Sorry to revive an older post, but I'm having same issues described here and wanted to try to continue the conversation. My issue is with the left bonus. Any time the left bonus advances past 5k, the machine automatically counts down the bonus right away. The OP mentioned something similar earlier, but I don't see much conversation on that (I'm guessing that issue kind of fixed itself with other fixes he tried). Anyway, I'm hoping someone has an idea. It only happens when you score a bonus increase on the left side (the right seems to be working fine). It doesn't happen when I manually move the bonus up on the stepper unit, only when scored from the playfield. I also noticed that when a left bonus is scored, the Left Bonus relay pulls in and holds (the right bonus relay doesn't move when right bonus is scored). I've been through all the paths a bunch of times and just can't seem to see anything. The fingers on the stepper seem fine also. Clearly something must be shorted to cause the bonus to automatically countdown as soon as bonus is scored. I just can't find it. Any ideas?
Thanks HowardR . I went through all of these paths again with no luck. The only thing that prevented the automatic bonus countdown was blocking the Left Bonus Relay's own hold switch. The relay still pulsed, but didn't hold on to allow the bonus to count, so I don't think that's it.
I'm wondering if the left bonus stepper has been messed with. I already found a moved wire that was causing other issues and fixed it. The W-B wire was tied directly to the W-G, not the other side of the MB switch as it should on the Zero Position Switch (picture attached). There is also a black wire that loops around to the back switch which seems right. I now notice that there are two W-B wires tied to the same spot on the stepper board (other picture). If you can see, one of the wires looks like the casing has been pushed back, so it doesn't look original. I'm wondering if this wire has been moved as well. I guess I could de-solder that wire and see what happens. Though I'd check for other thoughts first. Does anyone have similar pictures on a working machine so I can compare?
IMG_2370 wires (resized).jpgIMG_2372 left switch (resized).jpgWanna join the discussion? Please sign in to reply to this topic.
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Columbus, OH