1994 E320 Blower Control

[E320A]

1994E320 blowercontrol
What a great place with so much info and help. Have read through the info on the Climate controls and have done the following:

Have an E320 1994 with dust filters. Blower was only working on low and now does not work at all. Have checked the ACC control unit in dash with the working one from my E420 and still nothing. Next took apart all the stuff that hides the blower motor and checked that, it runs just fine. Checked all the fuses including the ones outside the main fuse box, all replaced with new fuses. Also checked that the power is going to the blower motor and everything seems OK. Now I think it is the Blower motor regulator ($300) and before I order a new one, I would like to know if I should check anything else that could cause the problem.
Thank you in advance for any advice.