More METLE issues - strange Snake behaviour

[Pooman2084]

Hey guys,

I finally got my MET back up and running after replacing most of the LED boards.

Everything seemed ok initially, but I am getting erratic Snake jaw behavior. It seems like it is dropping at random during game play (not during MB interestingly - seems ok then). It also drops immediately you start a new game, even before the ball hits the shooter lane.

I removed and checked the switch that shows that the ball is in the snake lock as that had been flakey for a while, but it all checks out ok in the switch test with no 'phantom' registers after a couple of hours. The snake test itself indicates that everything is working as it should.

If I start a game, 80% of the time closing an orbit switch drops the jaw, but no other switch seems to affect it.

I was getting the bottom bumper firing randomly after it had been on for half an hour or so, so they might be connected? Again all is ok in test mode, and the switches seem to have normal gaps.

Phil has offered to look at it in his lab, but I couldn't fit the damn thing into the back of a new XC90 so had to abandon that idea (and that it is a 220 mile round trip). Is there anything I should be looking at as I'm pretty lost as to where to go from here?

As some background, the 5V rectifier blew previously and took out the LED boards and ColorDMD, but these have been replaced or repaired now.

Many thanks,

Lloyd

 

[Pooman2084]

Hopeful bump.....

 

[Wizcat]

Sounds like switch issues to me. Possibly caused by vibration of other solenoids firing?

One way to isolate that as the cause would be to disable the switches (with tape, or unplug if possible). Then play a few games and see if it 'cures' the issue.
If the jaw still moves randomly when the switch is disabled, you know its a fault closer to the boardset.

 

[Moonraker]

I've a sneaky suspicion that it's a MPU fault...

 

[Pooman2084]

Thanks for the info guys. I've been working in Germany this week, but back today, so hopefully can investigate more over the weekend.

MPU is suspicious Peter as I obviously had the problem with it that kicked off the whole sorry saga. I think a good way to move forward is to desolder the jaw switch and see what happens. If it goes away then we have a good clue as to where the issue lies.

Would the LE MPU be a straight swap with a Premium do you think as I have found a local pinhead with one?

 

[Moonraker]

Thanks for the info guys. I've been working in Germany this week, but back today, so hopefully can investigate more over the weekend.

MPU is suspicious Peter as I obviously had the problem with it that kicked off the whole sorry saga. I think a good way to move forward is to desolder the jaw switch and see what happens. If it goes away then we have a good clue as to where the issue lies.

Would the LE MPU be a straight swap with a Premium do you think as I have found a local pinhead with one?

After playing mine a few times I think your's is a faulty metal jaw switch (like a lip in front of the jaw).

Yes the mpu will be a straight swap for a premium one.

 

[Pooman2084]

Could be I guess as I was working in that area. Strange it is triggered seemingly only by orbit and ramp shots though. I seem to remember there is a screw to adjust the height / angle of the jaw, maybe that needs an adjustment. Thanks for the tips, I'll report back after I have another play with it. I have enough to move forward with it now at least.

 

[Pooman2084]

Also I couldn't find a relationship between the snake and ramp / orbit shots in the switch matrix so a wiring / matrix issues seems unlikely.

 

[Moonraker]

Also I couldn't find a relationship between the snake and ramp / orbit shots in the switch matrix so a wiring / matrix issues seems unlikely.

Possible vibration on the switch (hence look closely at the switch) otherwise it's likely to be a board issue.