Light Fixture Troubleshooting

Have a light fixture that is labeled as a Pac Fab No. S-994149 Label #98700600, but can't find anything via Google that matches any of the numbers on it. It appears to be the same as a Pentair Sam Spectrum Amerlite like this one - http://www.poolpartsonline.com/p-134...ite-parts.aspx.

So the problem is neither the light or color wheel motor come on at all. I pulled it up on the deck and disassembled it. Used a no-touch voltage tester to check the power cord, light sockets, circuit board, power feed to the color motor - everything shows it is getting power when the switch is on.

I did notice that the lights the previous owner must have replaced the originals with are not quite to spec, though they both appear to be fine. No signs of being burned out. They are GE 71w EYC MR16 instead of the 75 watt, EYC, MR-16 specified as the correct replacement bulbs above. The GE bulbs in there now appear to be general purpose bulbs aren't specifically made for underwater use (and are less than half the cost). Not sure if that would matter, is it possible the whole unit won't come on if the bulbs aren't the right ones?

Everything else looks just fine, it was bone dry when I opened it up, no signs of any leakage or corrosion. No indication anything had shorted out, etc.

Any ideas on where to go from here?