Can you tell if a high current flows when you are attempting to rotate the motor in the direction it doesn't go?
Looking at the 2 diodes D1000 and D1003, when the motor is turning, one diode reads 0V and the other 24V. This indicates the appropriate mosfets are turned on.
When attempting to turn the motor in the other direction, the voltages should be 24 and 0, but you get 10.6 and 0.
If there is a heavy current flow, this would be indicative of something shorted.
However I think it is more likely that one of the mosfets isn't being turned on properly.
When the motor is working, the top 2 mosfets are on. It appears in both cases that Vgs is 6V
In the case when the motor isn't working, the bottom 2 mosfets should be on.
We're seeing only 1.8V and 0.4V Vgs. I suspect that there's a driver in common for the bottom pair of mosfets and it is damaged.
See if you can trace where the gate of these mosfets (T1002 and T1009) are connected to (they are isolated from each other, but it would not be unusual for them to go to the same driver chip). There may be a low value series resistor too.
Actually I note a diode and a resistor near each mosfet. These are possibly connected in parallel and connected between the gate and the driver.
I also note that there is not a pair of similar devices close by the mosfets. The driver may be the 8 pin or the 14 pin device.
The 8 pin device appears to be an LM358 -- I'd not suspect that at the moment.
The 14 pin chip is a quad NAND gate -- probably not that either.
That really only leaves the 4 transistors just below it. These *may* be used to switch the mosfets, and *may* be worth checking. -- I'd have a quick look at the voltages on their base, emitter, and collectors in the two cases and see if there's any clues there.
Maybe you can determine if they connect to the gates of the mosfets.
Also, I note that some of the capacitors are leaning over. Check the bottoms of them to make sure they're not swollen or leaking. It is unusual that they're not flush with the board.