PCB Repair: Legend of Kage
Problem
Won’t accept coins.
Diagnosis
I received two untested Legend of Kage boardsets to look at. Though it turned out there was nothing wrong with either, I figured it was worth documenting a couple of issues I encountered while testing them.
Legend of Kage uses the ‘Taito Classic’ pinout (like Bubble Bobble, Arkanoid etc.) but the video board must also be powered separately via its [T] edge-connector; there is no power supplied over the ribbon cable connecting it to the main PCB.
Once I had both boardsets running on my test bench, neither would accept coins other than from the service coin input. As with other Taito games of the era, coin I/O is handled by the PC030 hybrid module:

The PC030 will not enable the COINA/COINB outputs if no coin meters are connected. The Romstar Bubble Bobble manual helpfully states that to run the game without coin meters, wire jumpers must be installed at points JPA and JPB.
On the Legend of Kage PCB, JP4 corresponds to JPA, while JP5 corresponds to JPB. Fitting wire jumpers to each allowed both boardsets to recognize coin inputs.
Fix
Add wire jumpers to points JP4 and JP5.