JD Tilt Warning - Solved

[mark adams]

Hi All,

My JD activates the plumb bob tilt whenever the 3 target bank is triggered, in switch test it operates both the target switch and plumb bob tilt simultaneously.
Checked the diodes and wiring on the 3 bank target , no shorts and all diodes the right way round.
CPU board is a rottendog but the fault was there before it was fitted
Any thoughts where else to look??
Judge drop down target E doesn’t activate but that’s probably just the opto and likely not related.

TIA

Mark

 

[Spandangler]

There is some matrix on YouTube that will highlight the dodgy diode if you know which switches are triggering it. I’ll try and find it

 

[James]

Basically its a square... so... any of these could have a short on them, luckily for you - there are many not used switches in that area.. ish.



So it is any of those 6

 

[Spandangler]

That’s the one James. As I can’t actually count past a hundred, I find that video mind blowing

 

[mark adams]

top stuff, thanks fellas, I'll report back when i've had a look

 

[Moonraker]

I'd start here to find out if it's a switch or board fault:
http://pinwiki.com/wiki/index.php?title=Williams_WPC#Switch_Matrix_Problems

 

[mark adams]

Thanks everyone,
Drew a blank with the 6 suspects above, some of them are optos and therefore no diode, the others all buzzed out okay with one leg disconnected.
The opt for (E) drop down target still doesn't work also, i switched the two opto driver boards under the playfield, made no difference.
This is all with a new CPU board fitted, fault was apparent with the old one too so fairly safe to rule out the CPU board.
I'm going to try replacing the opto (E), although its a larger than normal opto so i'll have to order one.
I can't see it being that causing the original fault.
I'm scratching my head now....

 

[pinballmania]

Can you post pictures of the switch matrix test when the drop targets are up and when each one is down?

 

[mark adams]

in sequence, the last drop down target acts as though it is activated constantly

 

[pinballmania]

Why is switch 28 showing closed. ? That was ball on magnet and should be unused. Whatever, it shouldn’t be permanently closed. If someone has shorted the unused connector with a wire to stop the spurious switch 28 error them when switch 18 three bank is operated it will form a square with 18 28 and 24 and causing a ghost at 14 which is tilt.

I think.

 

[pinballmania]

Such a short could also prevent the other switches on the row working eg. E in judge. Or it could just not be working.

 

[mark adams]

is it possible switch 28 is a result of something else in the chain, subway 2 seems to activate two switches but its so quick i can't read what the other one is.
I have had the subway switches out and checked the diodes off the switch, both okay, three targets trigger the tilt, subway 2 triggers something else as well, Judge E doesn't work at all, Captive ball 3 however behaves itself completely... I metered Captive ball 3's diode too, all okay

 

[James]

Take all the balls out and reset the targets - then the only closed switches will be normally closed, which would point to a diode issue on one of those. visually check the switch that pinball mania was referring to to see if someone has shorted it as it sounds like it shouldn't ever close???

I had a similar issue with WPT - turned out it was the flakey opto causing havoc, which in your case is E and giving all sorts of spurious switch errors. I would replace that as you said you would. That was causing switch errors outside of a normal switch matrix problem.

 

[pinballmania]

What does subway 12 trigger. ? If you flick it Multiple times in switch test you should be able to see which wrong square is flashing in sync

 

[mark adams]

okay, subway 2 triggers inside right return as well... the plot thickens....

 

[mark adams]

Found it, embarrassed to admit it was something i had done too.
The Left pursuit gantry was removed when i got it as the bracket had broken, on inspection the left was also broken, i removed both and fashioned a new bracket from some metal and refitted them. However on refitting the left gantry i had plagued it into the nearest same shape connector (which i now think may have been switch 28) so the flashers didn't work but that was on my snag list for later.
On closer inspection, there was another same shaped plug tied up in the wiring that after plugging the gantry into, the flashers now work as do all the switches including Judge E.
What a pillock....
Thank you everyone for your valuable input, it is very much appreciated and something that makes this forum stand out from any others.

 

[Happypin]

Found it, embarrassed to admit it was something i had done too.
The Left pursuit gantry was removed when i got it as the bracket had broken, on inspection the left was also broken, i removed both and fashioned a new bracket from some metal and refitted them. However on refitting the left gantry i had plagued it into the nearest same shape connector (which i now think may have been switch 28) so the flashers didn't work but that was on my snag list for later.
On closer inspection, there was another same shaped plug tied up in the wiring that after plugging the gantry into, the flashers now work as do all the switches including Judge E.
What a pillock....
Thank you everyone for your valuable input, it is very much appreciated and something that makes this forum stand out from any others.

And there was me watching this outcome with great interest just in case it happened to my JD.
relief I’m sure ?