If this happens when A/C is selected, you could have two possibilities. The first could be low refrigerant charge. The fact that the drivers side blows warm, is because it is furthest from the evap core. The second is a faulty air mix actuator. Often times if the air mix actuator overtravels, or falsely triggers an overtravel, it will default to full heat.
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Tuesday, July 13th, 2010 AT 11:20 PM