Thanks for taking a look and possibly helping me. I just picked up a Vector and none of the displays work. The F1 fuse was blown on the solenoid driver board. The previous owner stuffed a 3AG 1/4 amp in the 8AG fuse holder. It looked to be making a solid connection but the fuse was blown. I put another 1/4 amp fuse in the holder (3 AG, I do not have any 8 AG) and that blew on start up also. I checked T2 at the transformer board in the cabinet and I was getting 240V. I checked T2 at the solenoid driver board and I was also getting 240V. I got a reading of 240V at the bottom leg of the fuse holder also. I keep seeing these test readings at the solenoid board should be about 175-190 volts. I included 2 pictures of the solenoid board with some suspect heat marks and a solder joint but am not sure how to proceed. If I turned down the dash pot to 190 would it quit blowing the fuse or do I have a bad resistor or cap? Or am I completely on the wrong track (very likely....LOL). I plan on modifying the fuse holder to fit a 3 AG since I have it out of the back box also. Any help guys would be greatly appreciated!
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Thank you so much for the quick reply! I have trouble identifying all three trasistors. I see q22 plain enough, but I am looking at the schematic and I still cant find them. Am I correct in thinking they are on top of the heat fins? I have the part numbers, I just wanted to be sure where they were on the board. Thanks again barakandl !!

Sounds good. Thanks for the reply. I will order those also

I definitely will, thank you. What is considered to be a good ESR meter(?) these days?

Gotcha, thanks.

I unplugged all the displays and plugged one in at a time and found two that were blowing the HV fuse on the solenoid board. The other 4 displays now work fine with no obvious issues. I then switched one of the working displays to a non working display slot in an effort to check the wire harness and the good displays worked in the new slot, which I think would rule out the harness correct? I took out the two displays and did a visual inspection and they are very dirty with what looks to be mouse poop stuck underneath some of the pins even. I did not see anything burnt up or any obvious cold solder joints but there was some slight corrosion on some of the resistor and transistor leads. What would cause a display to blow the fuse? I have searched for advice on this forum and youtube but most post or videos are about missing digits or segments of digits, not a display blowing a fuse. Also, how can I clean these displays up. The are pretty filthy LOL.

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I have re-read this 10 times and it is not helping, LOL. I only half understand what you are saying. (I'm really sorry or my ignorance and really appreciate your patience and all the help you have given me). Do I check for resistance of the high voltage rail on the display? Should I plug in the display with the power off to do this or can I do this on the bench with a working display and a non working one? I see VR1 on the score pcb but dont know how to test it. Again, sorry

Ok, on the VR1 I get .615vdc on the good board and on the two bad boards I get .605 vdc and .616 vdc. Those should be fine, correct? When checking for a short, I believe the first pin is the high voltage one. I checked on the game harness and the first pin was reading 180 vdc and I believe the the 13th pin next to the key pin is ground. No continuity on the good board or the bad boards. Although on one bad board I did get continuity on the second pin and the ground pin. I can't seem to find a schematic that shows the pin layout on the display pcb's.

I will get on it when I get home from work, thank you for all your help guys!!

Solved, and thank you guys for all your help!

I ordered a Big Daddy high voltage regulator kit and reflowed the pins for the displays.