Nope.

Flipper rom does not refer to anything flipper related other than that it's a pinball rom ie intended for a game that happens to have flippers.
Your game wouldn't boot if the rom was bad.

If they aren't firing with voltage at the lugs you have it either wired wrong or the coil is defective when you manually ground it. You sure your end of stroke switches are clean new ones sometimes aren't.

In order to verify your wiring, we'll need to see the other side of the coils, where the diodes are located.

I think the wiring looks correct.

You can try using an alligator jumper to briefly ground the middle lug of either flipper coil and it should fire. Grounding the non-banded lug on the flipper coils should also fire them. *Don't ground the banded/power side of the coil, it will blow the fuse for the flipper circuit*

That may help us narrow things down further.

For more educational reading, I highly recommend clays guides located at pinrepair.com. Using your browser, search the Williams system 3-7 repair guide for "Flipper Diagnostics" and begin reading at "If your flipper(s) don't work at all:

http://www.pinrepair.com/sys37/index3.htm#flip

I've been down the same road, and if you've tried everything on that list--what fixed a similar issue on another system 7 game i was working on: replace connector 3J3 on the power supply, male pins and female connector. Fingers crossed, that'll get you back in business. Good luck, keep us posted!

Nice!! I was hoping that would fix it, because I was out of ideas after that, lol! In my experience I found replacing the header pins to be the best course of action long-term. In fact, I found a noticeable amount more power from the flippers after replacing the headers. Might be worth considering, though it sounds like you might be good to go with a simple reflow.

Good work!

I'm curious to see if you notice any further improvement with new headers.

It's funny, you went down pretty much the exact same diagnostic path I had taken a few years back helping my buddy out with the flippers on his newly-acquired Black Knight. After trying everything on that list and coming up empty-handed, I finally tried replacing 3J3 and that fixed it. I had been focused completely on the ground side of the equation because I was getting proper voltage readings on my meter and could get the coils to fire by grounding them directly.

When I got home that day, I pulled the power supply board from my own Black Knight and discovered 3J3 had dull looking pins at positions 4+5 (voltage supplies to the left and right flippers) ...after re-pinning that connector I finally feel the game has the flipper power it was supposed to have all along. Previously, I'd messed with EOS adjustments, new cabinet and EOS switches, flipper rebuilds, and anything I could do to improve the flipper power...but once I replaced the headers at 3J3 it was all finally working properly.