Hi thanks for the reply, I thought that it might be one of those, but I think the problem is in the steer control card. I f you unplug the card then the drive seems to work fine. I talked to the local toyota guys and they never heard of this problem. The problem with these machines was they were so reliable, no one knows how to fix them. Thanks Brent

It is an open DF diode. There is an upgrade diode kit available from Toyota

I was wondering if you got this problem solved, I have exactly the same problem.
any help would be great, thanks Brent

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It sounds like it is struggling in fwd as if low volts to motor, but rev makes that typical whine as you press on the accelerator on these toyotas. Low pitch to high pitch the faster you go. wheels turn very slowly in forward when drives are raised. You can hear the contactors open and closing as you turn the wheel.

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can you further define the "whine", and compare the whine to any noises you hear in rev.?