What's new

System 11 Phantom switch?

ronnie63

ronnie63

Site Supporter
Joined
Jun 8, 2015
Messages
2,217
Location
Scotland
Looking for some advice please! The game is Road Kings, during the game if I get a ball locked in the center eject (sw38) which is locked for multi-ball and then the 2nd ball drains outhole (sw40) I get a tilt! both switches are in the same column. I guess it's a case of looking for a bad diode on a switch? But I also read about the resistor packs on the driver board? Just not sure where to start and don't want to be chasing my tail for hours!

Thanks Ronnie
 
Hi, Ronnie,

Have a look at the switch matrix chart; with the two properly closed switches and the false tilt, plot a 'rectangle' on the chart. Whatever the 4th corner of this is, is the likely point for a short circuited diode. Correction - the faulty switch is opposite the false/phantom switch.

The conditions where the problem occurs can be replicated in the 'Switch Levels' test. In your case, this would leave the situation in place, rather than having the out-hole coil kick the drained ball away.

Update - the chart for Road Kings shows a possibility of the rectangle being Centre Eject (38), Outhole (40), Playfield Tilt (46) and Right Flipper 'Lane Change' (48).
 
Last edited:
  • Like
Reactions: DRD
Thanks jay for the help so looking at the chart it would be right flipper eos (sw48) if it was playfield tilt(sw 46) rather than plum bob which is another switch.

sm1sys11.gif
 
Yes, assuming it's playfield tilt, which I hadn't thought of at first - the cone tilt couldn't form a rectangle with the two proper closures. Switch Levels would show which of the tilt switches you're actually having falsely detected. With the two balls placed as described, and the flipper raised, if Playfield Tilt is also listed on the display, then that's the rectangle formed.

Another check would be to try the 1st ball in the left eject, 37, with the outhole and flipper, which if we're right would produce a false 'Left 10 Point' (45).
 
  • Like
Reactions: DRD
Thanks Jay, think I'm getting somewhere, with 38,40 and 48 closed I'm getting 46 playfield tilt! so that's right flipper up, the center kickout and center drain, I never knew the flipper played a part in the fault. Right just need to figure out the culprit now!

Thanks Ronnie
 
Apologies, Ronnie, I should've said that the false switch appears diagonally opposite the faulty switch, so here it's the outhole switch.
 
  • Like
Reactions: DRD
Thanks Jay, no problem. Switch 40 outhole checks out fine, the diode reads good? should I replace it to rule it out?

Thanks Ronnie
 
Yes, I'd remove it and try another. Simply taking it out of circuit wouldn't really prove much, since then the switch wouldn't register at all.
 
Jay Walker said:
Yes, I'd remove it and try another. Simply taking it out of circuit wouldn't really prove much, since then the switch wouldn't register at all.
Click to expand...

Thanks Jay, I replaced it but results are the same! Nothing is ever simple
 
Could this be down to bad resistor packs on the driver board? Not sure where to check next.

Thanks Ronnie
 
Ronnie, I had a similar fault on a Bally SS which turned out to be the cap across the plumb bob tilt switch. If you have caps across the switches involved it may be worth clipping them to experiment.
 
astyy said:
Ronnie, I had a similar fault on a Bally SS which turned out to be the cap across the plumb bob tilt switch. If you have caps across the switches involved it may be worth clipping them to experiment.
Click to expand...

Thanks astyy will have a look at that but as far as I remember it was just diodes
 
Is this a new development or always been there? Just wandering if its possibly a wiring fault.
For example, is the diode on the outhole switch definitely wired in series rather than parallel with the switch?
 
backbox said:
Is this a new development or always been there? Just wandering if its possibly a wiring fault.
For example, is the diode on the outhole switch definitely wired in series rather than parallel with the switch?
Click to expand...

Thanks for the reply, it's new to me but the machine has only recently been cleaned up by my, it's been sat unused for years! I have looked to see the diodes are the correct way round but not looked too see if the wires are the right way! I will check on that as I must be missing something?

Thanks Ronnie
 
I have checked all the wiring and diode orientation on that row and column and it all checks out fine.

So I moved my attention to the resistor arrays and SR17 which sits above those ceramic resistors is a 4.7k array they all read fine apart from pin 10 which is reading around 2k

Also both SR9 and 10 should be 1k but they are both reading 2.5k? but they may read ok off the board?

Thanks Ronnie
 
So kinda stuck now! I replaced SRC6 with 1k resistors thinking this would fix it but it never. I don't fancy replacing all the SCR's with resistors as it's a bit fiddly and does not look the best, but if I thought they were at fault I would order some.

Thanks Ronnie
 
Right I have been really stupid! it was outhole sw40 all along! it was wired wrong way round (not by me) I missed it as the 2 wires look identical in colour which is strange as most of the other rows are green with a stripe. Anyway glad it's fixed.

Thanks for all the replies and to Jay for nailing the fault from the start.

Cheers Ronnie

"Cruise Again"
 
You must log in or register to reply here.
Back
Top Bottom