This just happened this morning. Had good heat yesterday and no problems til now.
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2005 Mercury Mountaineer Question: I have heat on the passenger side but not the drivers side. Can you help me out?
Answer #1Momentum Automotive (15 Answers) , Harlingen, TX - (956) 329-7244momentumautomotive October 01, 2013, 16:13Enthusiast
There is a blend door motor on the pass side of the vehicle which varies the hot and cold air. this motor has quit working, most likely the plastic gears inside the blend motor. it will have to be replaced with a new unit.
these are available through most parts houses.