Check pins 2 - 17, these are the outputs. Make sure you have 5V supply to the PIA first of course.

In all honesty though, if test points are OK except TP (4?) - Blanking. I would be looking there.

Blanking signal makes sure you have a good 5V supply, if not it shuts CPU down to prevent damage. All this circuit does is "test"the 5v. Problem is that if the blanking circuit fails then the good 5v cannot get through to CPU and game wont boot. By jumping the 5V to pin 37 on interconnector, all you are doing is by passing what maybe a faulty circuit. If its not faulty you can do no harm as the blanking itself is working and rendered CPU asleep. you can only overrride the Blanking IF it is faulty.

Turn game off - jump the 5v to pin 37 and turn game back on