what is wrong with the air conditioner on 2000 Mercedes-Benz ML320

while traveling down the road it blows cool air most of the time, but stop at a light or just idle and the air blows hot..i had it recharged at an a/c repair shop each year for the past 2 years.it cooled all summer last year, but not doing much of a job this year. this problem happens all the time now

by in Denton, NC on July 19, 2012
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1 answer 3 comments
ANSWER by , July 20, 2012
Check to make sure the blower motor (fan) is running because it sounds as if it is not operating.
COMMENT by , July 20, 2012
i will and thank you, but if the fan is not running wouldnt that make my car run hot[over heat]. today the a/c was cold enough i had to turn it down because it got to cold. i will check this out and again thank you so much.have a blessed day!!
COMMENT by , July 21, 2012
Not talking about the engine cooling fan, but the small blower motor that blows the air through the small ductwork of the car's heating and a/c system. To test the blower, turn on a/c or heat and cycle fan blower switch through all settings low to high and feel if the air's force through the vents increases as you go from low to high without the car moving.
COMMENT by , July 21, 2012
i did this and they do all work.thank you for the suggestion.