My Bigfoot head doesn't turn. I've checked the motor with a 9 volt battery and it works, the red and white leads to the motor are intact and the bi-directional motor board is getting it's 12 volt and the LED is on. The C2 capacitor doesn't look like it leaked and I checked continuity on the traces that run under it. The only thing that seems a bit off is that diodes D1, D2, D3, D4, D7 and D8 test a bit strange in circuit. They all show the normal .6V tested in diode test on my multimeter in one direction but the other way they show 1.25V.
Could anyone confirm that that is normal or are they all suspect?
Thanks!

Thanks Zaza, the search continues!

I don't see any problems with the C2 and have checked continuity on the two traces that run under it. Replacing it is an option but I want to see if it's something else first.

Looking at the schematics I noticed that two wires were reversed in J1. The blue-red and blue-brown. I reversed them but it still isn't working.
Next I'll try reflowing some solder joints...

Grounding J1-1 doesn't do anything and there is no voltage on J2-1 and J2-4 to the motor. The motor works when connected to a 9v battery.

I will try reflowing the solder and otherwise ask if I can try the board in Robin's Doctor Who. Maybe that will shed some light on the situation. Thanks Zaza!

Reflowing the solder joints didn't help. I'll remove the C2 now. PinWiki says it's not even needed. Maybe that'll help.

Continuity checked OK on the traces. No sign of leaks.

Bi-Directional Board (resized).jpg

Bi-Directional Board 2 (resized).jpg

Hope to see you next time then!

Well, replacing C2 and the LM339 didn't fix it...

Bi-Directional Board 3 (resized).jpg

I put the game in head test and put my DMM black lead on pin 1 and the red on pin 2. In Clockwise test it reads 12.1V and in Counterclockwise it reads 11.8V. It doesn't seem to reverse.

Just put my board in a Doctor Who and it works fine. So back to connectors and wires...

Replaced the J122 connector on the Power Driver Board this morning and success!!! The head now turns! The only problem is that it only turned clockwise.
I remembered that I 'corrected' the placement of the blue-brown and blue-red wire between J122 and J1 on the bi-directional board.
According to the schematics in the White Water manual J122-1 should go to J1-2 and J122-2 to J1-1. This turns out to be wrong. When I put the wires back how I found them the head turned both ways again. SO J122-1 goes to J1-1 and J122-2 to J1-2.