Jurrassic Park Back lights...Lower string not lighting...

GameyMcGame

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Jurrassic Park Back lights...Lower string not lighting...

Anyone have ideas? I've check the fuses, checked for burnt connections, loose wires etc.

Thanks
 
I had the same problem on mine. It was a cold solder joint on the PPB. The connectors were fine. You'll probably have to pull the PPB and inspect it.
 
Ok, so I tracked it down to the PPB, looks like the molex is totally fried. Pull the PPB board, check the solder and then replace the molex. I didnt see molex 'sizes' in the manual, anyone know which size it is? Thanks for the help
 
Ok, so I tracked it down to the PPB, looks like the molex is totally fried. Pull the PPB board, check the solder and then replace the molex. I didnt see molex 'sizes' in the manual, anyone know which size it is? Thanks for the help

Replace the headers AND the pins. The size is .156".
 
Thanks for the help everyone. Re-soldered the pins (well, just heated them up and added some new solder) and the lights work. Voila. Thanks!

Now, if I can just figure out why at certain times areas of the DMD get dark (like a dark shadow moving across areas). Ugh!
 
Have you checked the voltages to your DMD? If it is getting low voltage, or if it is on the way out, certain animations will look dark.
 
Have you checked the voltages to your DMD? If it is getting low voltage, or if it is on the way out, certain animations will look dark.

Will check it tonight...Its as if sometimes a black cloud rolls around a certain area. But in test etc. (and with most animations) it totally bright and vibrant...
 
Sounds like you are good there.... I ran into something a bit similar with an older rom revision of JP....

Do you have another DMD to drop in there to test...?

Dumb question...I do have a DMD in another pin...How do I swap them? The connections dont look to match up?
 
I'm asking about the high voltages. You should be getting -110, -98, and +68 at the DMD itself. The +4.81 to the controller is on the low side. Double check all your voltages, at the power supply, DMD, controller board. You may need to clean or replace some connectors.
 
Edit: See post #32, the PS was most likely not under-volting the DMD.

Your display is being under-volted, which can cause certain areas to appear dim and shaded. -98v is definitely low, 68v is a little low, and 5v is a little low although this shouldn't make it dim. An older display can be dimmer to begin with due to age, and add low voltage on top of that and you definitely will see dim portions at certain times.

Try re-seating the connectors and re-check the voltages. If that helps, you may need to clean connections or maybe re-pin some connectors. If that doesn't make a difference, check voltages directly on the power supply. Pinrepair.com will tell you everything you need to know.

I'm guessing that the problem lies with either the connector on the DMD, or the connector on the power supply, or both. Since all the voltages are a little on the low side, it makes me think the problem is a connector rather than the high voltage portion of the power supply.

I'm betting that after you get the low -98v and 68v solved, you'll have a nice looking DMD.
 
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Your display is being under-volted, which can cause certain areas to appear dim and shaded. -98v is definitely low, 68v is a little low, and 5v is a little low although this shouldn't make it dim. An older display can be dimmer to begin with due to age, and add low voltage on top of that and you definitely will see dim portions at certain times.

Try re-seating the connectors and re-check the voltages. If that helps, you may need to clean connections or maybe re-pin some connectors. If that doesn't make a difference, check voltages directly on the power supply. Pinrepair.com will tell you everything you need to know.

I'm guessing that the problem lies with either the connector on the DMD, or the connector on the power supply, or both. Since all the voltages are a little on the low side, it makes me think the problem is a connector rather than the high voltage portion of the power supply.

I'm betting that after you get the low -98v and 68v solved, you'll have a nice looking DMD.

Pulled the connectors, used some superfine sandpaper on the posts and still the same reading. Actually, the power at the posts (without the connectors on) read the same as at the DMD board so I think there is somethign going on before the DMD board beyond just the connections...
 
Doesn't sound like the connectors, too bad it wasn't an easy fix. Time to read up on the HV repair portion of pinrepair.com. I hope the low voltages are what is causing what you are seeing because if so it should be a relatively inexpensive fix.
 
Doesn't sound like the connectors, too bad it wasn't an easy fix. Time to read up on the HV repair portion of pinrepair.com. I hope the low voltages are what is causing what you are seeing because if so it should be a relatively inexpensive fix.

And if not, it looks like this may be a plug and play replacement? $79 may be worth it to not have to deal with it...

http://www.arcadeshop.com/parts.htm#Pinball Parts
 
Well, yeah, but it is probably <$5 in parts to fix. And the $80 aftermarket power supplies have marginal high voltage sections. I fried a DMD with one. My first choice would be to fix what you have.
 
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