I had the opposite scenario. Blower quit last December and I spend a month with the SD in the cold.......down to 12°F. at times.......no blower.

Test the blower itself, first. If it doesn't work with 12V applied, you found your problem.

But, if it does work, you've got three more possible culprits:

1) CCU
2) Blower controller
2) Blower resistors.

Normally, if one of the resistors fails, the blower will run on certain speeds but not others.

In my case, I swapped the CCU and that was the culprit. Swapping blower controllers made no difference.