@Stuey81 , did you get the issue resolved? I have exactly the same issue where all actuators work fine in the relearn mode, but it keeps throwing DTC#B0253 which indicates the actuator on the drivers side needs to be replaced. I purchased a new actuator and plugged it in and it does exactly the same thing as the original one.
Sorry for the delay in replying, but YES! i did manage to find the issue. It turned out all the actuators were fine and working perfectly. Apparently one of the rods that goes into the HVAC centre ducting had popped off, so when the car went through its relearn process, it wasnt actually moving the thing inside that it was supposed to, even though visually you could see the actuator go through its full range of motion, and the lever it was connected to moving as it should.
So the actuator was good, the lever it was connected to was moving, but out of sight, the thing the lever actually rotated had popped off.
I asked the guy at Holden for their best gun mechanic, and im glad they provided me with him, as i never would have found it, and neither would some first year apprentice mechanic. When your paying $160 an hour for diagnosis, you want a pro on the job.
So yeah, its all working great now.