Make one of these to save on fuses. http://www.pinwiki.com/wiki/index.php?title=EM_Repair#Electrical_short_troubleshooting_Fuse_helper

Two different circuit boards...you may want to google the two different part numbers to see if there are specs on them, or other posts on them. Numbers look like they are on bottom left "PB...."

If two displays are not the original parts then combined they may draw more power than the originals and are blowing the fuse... not likely though if you've had them for a while.... probably something went on one of them.

If both seem to be affected at the same time then I'd also look at the schematic to see how the wiring runs and if those two share a common path or wire... could be a short in wiring connecting them both. If more than one thing is busted at the same time look for what's common to both.

Ah! Different story. Find out if the displays are even compatible with that game and what the pinout signals are for each.

I'd disconnect all connectors... see if it powers up without blowing fuse. Check resistances on each board from each power supply pin to ground (if there's more than one voltage applied to one board) to see that nothing is shorted to ground.

Do you have schematics for your game?

I'm assuming if the keys on the connector fit and you can plug in the cards that they should be compatible. Can't find much online against the two different board numbers. I'm out of town but will check which ones I have in my Spider-Man .

Use dvm to see if there is a short from any power supply pin on the display cards to ground. Does the fuse blow right away with the two questionable displays connected or just after they've been on for a while ?

Do you have schematics? Hard to debug without schematics.

Slam Tilt switch problem? http://www.pinwiki.com/wiki/index.php?title=Gottlieb_System_1#Open_Slam_Switch

remember you can swap the 6 digit ones around ... swapping 3 with 1 might be a good idea.

replacing the orange capacitors ( 1uf 100v from memory - gpe sells them). *might* get the shorted ones working again

For reference my displays are three of PB00-D140-001's and one PB00-D140-021. None of them have the extra components on your -011 cards. I expect they are compatible though if the connector keys fit and permit you to connect them. If blowing fuse they could either have shorts on them or just draw more current than other variants and be blowing the 1/4 amp limit by a bit.

The 12v supply from the bottom board generates the 5v supply on the power board. The 12V LED is right across the inputs, so if it's out it's either blown or you're not getting 12v from the transformers on the bottom board to the power board.

Check the fuse on the 12v supply on the bottom board, and whether you're getting 12V AC from the transformers into the big diode bridge components and 12V DC out of the diode bridges.

The displays also get 60V DC ... since they are on for two of your displays that supply should be ok.

I found my PDF of the AS manual if you need a copy of schematics.

Looking at schematics more... the displays don't receive any 5v DC power.

They get 60v DC from the power supply board (small display only 42v DC) and 5v AC not DC and it's directly from the bottom board transformers (small display only 3V AC).

If your 12V DC and 5V DC aren't working then that's affecting power to the control board, which provides the data to the displays ... D1-D16 and a-g segment bits.

If you're really not getting 5v to your electronics then nothing is really working... mpu control board, driver boards, sound card... all run off 5V DC, so all dead until you get that supply up.

Afterthought... when you are checking the 12V AC and DC on the bottom board, disconnect J1 from the power board.

I thought I had blown the large diode bridge because my 12V wasn't there... waited for months to get parts from China, only to find out when I replaced it that the problem wasn't fixed. The diode bridge wasn't bad, it was on my power board which pulled down the voltage and made me think the diode bridge was shot. If I had disconnected J1 from the power board I would have seen that all my AC and DC voltages were ok on the bottom board.

Also recommend you disconnect the big blue cap C1 before checking voltages. If it's shorted it would drag down your 12V supply as well.

The schematics show "TP" or Test Points on the circuit board. When you look at the power board you should be able to find these, typically as either wire loops (for if you have clip on DMM probes), or in my case for Spiderman, little posts. They are clearly marked on the circuit board as well, indicating which voltage is at that test point.

Connect the "Common" probe of your DMM to the Ground Test Point, and the other probe to the test point.
Ensure you have the correct setting on your DMM, AC voltage or DC voltage, and a level that is the next one higher than the voltage you are testing (ie. setting 20V DC for signals that are 5V and 12V.... or setting 100V for signals that are 24V, 48V, 60V...)

When you are on the bottom board in the pinball box, there are no "Test Points", but everything is pretty clearly labeled (like on the fuses, and around the diode bridges), that you can use as test points. On the bottom board, there is a long strip of metal with lots of green wires attached to it... that is one of your main Ground connections. If you're probes don't have clips, it would be a good investment to buy a pack of wires with alligator clips on them. Put a clip on your Common probe, and clip the other end to a ground point. Then you only need to probe around with one, instead of trying to hold two probes on two places.

I expect you will quickly find that you have no 12V on that board, since the 12V and 5V LED's are off. Then you will need to probe in the bottom of the pinball machine where the transformers and fuses are to see if that's all working.

Apologies if I'm being too simple in my directions... not sure what level of experience you have, but since you're asking about where to put the probes, I'm assuming it's limited. Just let me know if I don't need to be that detailed for you and what you already know how to do.

Again, you'll have a hard time figuring things out if you don't have a wiring schematic. Let me know if you have them from a copy of the manual, or if you want me to send you a copy to print off.

Happy New Year!

If you really don't have any power to your D and a-g signals that control the displays then you could have anything on your displays. If it was a slam switch thing then the control board would need to tell the displays to turn on that specific way, and right now it's not likely that it can do that.

Power first...

I suspect that since you have two different board types they are just responding to the lack of control signals differently... one all blank and the other all on or rando.

Bottom Board Schematic and photo.
Power down before disconnecting or connecting any connectors.

Disconnect the Power Supply board (J1 on the Power board) before testing the 12V DC levels on the bottom board, in case the power supply board is affecting them.
Disconnect your displays, and check your 5VAC and 3VAC levels on the bottom board too... they go directly to the Displays... not through the power board.

Power down. Reconnect J1 and the Displays then power up and see if the 12V DC, 5VAC and 3VAC are still OK. Since two of your displays are on, you shouldn't have any issues with the 5VAC and 3VAC.

BottomBoard (resized).JPG

Powerboard Schematic of Test Points and Photo. Connect your DMM Common to TP3 (Ground).
Note that TP1 and TP2 are AC... use AC V on your DMM
Note that TP4 and TP5 are DC... use DC V on your DMM
Power down before disconnecting or connecting any connectors.
Disconnect J2 and J3 (Displays and other boards) before testing the voltages on this board (in case the other boards are pulling down the voltages)
Then connect them back up to see if it affects the voltage levels.

PowerBoard (resized).JPG

Be careful testing voltage levels around the fuses that you don't short adjacent fuses. Once I wasn't paying attention and accidentally slipped and touched my probe across two adjacent fuse leads, and fried some components on my power supply board. If I remember correctly, I think I connected the 24V to the 12V lines (B and D adjacent fuses in first diagram). Anyway... just don't do it... it makes it easier if you have the common/ground lead connected with a clip, and then you're only focusing on where to place the one probe.

... btw... Deathlok would kick Batman's butt... just sayin'.
https://comicvine.gamespot.com/forums/battles-7/batman-vs-deathlok-692274/

Be sure to disconnect the connector from the power board and check rectifier if you haven't already. I did the same thing, waited months to get the bridge chips from china only to find out it still didn't work. Bad power board circuit pulling down the voltage made the bridge look bad when it wasn't . I would have seen that if I disconnected the power board connector before testing the bridge rectifiers .

I also assume you checked the diode bridge AFTER you disconnected the capacitor... if the capacitor was shorted it could affect you diode bridge measurements too.

Reading that again... sorry to ask a dumb question but what do you mean by "ok in one direction but not the other"? Diodes sort of work that way depending on what you're testing and where your positive and negative probes are put.

With power off, cap disconnected, and connectors off of circuit boards you can check each diode in the quad in both directions. Compare what you see on the 12v bridge diodes to what you see on some of the other diode bridges that you think are good.

Apologies if you already know all that. Not sure what your experience level on diodes is.

Yes. Just pull the power connectors off any boards to rule out that they are affecting your diode bridge readings. If your capacitor is shot though it can also affect the readings. The bridge rectifiers may be ok. The testing procedures assume nothing else in the circuitry that could affect readings .. a shorted cap would.

If the cap is shorted you may find that after disconnecting it you power up ok. You'll need one long term to stabilize that 12v power but it should actually power up without it.

Yes. Mine is either an aftermarket board or reworked but I only have the single Prom in P1 with markings on it for both Proms (extra address bits). You can see extra components beside my P1 that are not in your shot. Looks like you'll need a set of proms.

IMG_1022 (resized).JPG

Flippers.com seems to have them... Burnaby BC.

Probably need to find out if you need 2 or 1 Prom. I'm sure there are lots of posts about the mods needed to use 1 Prom.

I got a sound card Prom from a guy in Toronto... I can check if he has game proms as well for games if you'd like. Let me know.