Passenger Van Rear Blower M Doesn't Operate At Low Speed Only

Passenger Van Rear Blower Motor Does Not Operate At Low Speed Only When Controlled From Either The Front Or The Rear Auxiliary HVAC Control Module (Part 1 Of 2):

Passenger Van Rear Blower Motor Does Not Operate At Low Speed Only When Controlled From Either The Front Or The Rear Auxiliary HVAC Control Module (Part 2 Of 2):