Hi all, I'm swapping out my heater core in my EBII mont after many years of putting it off. The heater would always only put out luke warm air. I replaced everything besides the climate module itself, it never put out any fault codes so I thought the core was corroded or partially blocked, it doesn't appear blocked (although pipe internals corroded as all hell) replaced the core anyway but I've noticed the blend door doesn't open?

Is it possible for the motors to seize? The door isn't snapped but I can't move the shaft/arm on the motor by hand, about to take the motor apart and see if I can unseize it. Cheers