I have a Millionaire that P1 and P3 displays are out on. When dark in room you can see the little dot of orange glow on bottom edges of P2 and P4 (besides the actual digits being lit) but P1+3 have no such sign of life, no glow anywhere, completely dark

Looking for things I can check / ways I can confirm they are bad before I buy new.

I do not have another machine compatible that I can swap things over to check. I'm a novice at best with electronics but I'm open to suggestions.

thanks for any insight

Thanks for the replying, I've read about the electric ball trick but I'm assuming you have to desolder each display before trying that so you don't fry anything.

Thats actually also why I want info about things I can test, I'm not sure something isn't bad up the chain so I'd hate to order a new display, install and fry it. thanks

Thanks Spy, I read about that and was going to check next time I have a chance. Was also reading about reversing the ribbon cable too.

Nothing in auto or manual display test, no digits no segments, all dark. thanks

Just to paint a more detailed picture this is what I know so far....

Reversing ribbon cable yields same results, P1+P3 still out.

No signs of life, digits or segments from display test mode, auto or manual.

I have continuity from all wire connectors going from display board to matching connectors on other boards

Coming into display board at connector 4J2 reads +4.9 , -103.6 and +106.9

ALL following readings where taken in display test mode with manual all digits/segments on and all displays constantly on at same time (another words not auto scrolling through and not digits turning off and on,)

Working P4 7 digit/segment display pins 7 and 31 read -65.4 while pins 6 and 34 read +58.8

Non-working P3 7 digit/segment display pins 7 and 31 read -94.2 while pins 6 and 34 read -71.3 ..... all negative readings???

Didn't know what pins on the alphanumeric were corresponding but probed all and was getting readings on the high ones up around +/- 94

Pictures below are pic 1 and 2 of P1+P3, flash and no flash ....can definitely see a bunch of speckles/dots in P1 not present in P2
Pictures 3 and 4 are of working P2 + P4, flash an no flash

although P2 is working it seems not solid at times and like its on its way out. Can definitely see what looks like burn in picture 3

thanks all for helping out! At this point i'm assuming displays will need to be replaced but as said before my biggest concern is if something needs attention up the chain so I don't install new displays or working old ones and just fry them.

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Unfortunately on this model the displays are all on 1 board so you can't easily swap them around via connectors. thanks

As far as I remember my nips are good, i'll have to look closer when I can. Header pins, connectors, joints etc. and all looked good, wiggles was the first thing I did with the connectors.

Does the duel negative readings on the non-working 7 digit dispaly (P3) mean anything?

And that all my readings are low on P3 and P4? Supposed to be +100v and -100v according to manual

thanks

I concur, thanks for the input!