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1999 Mercedes-Benz ML430 Question: In my 1999 ml430 when I turn on heat it blows cold air what can I do

 

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Seanluv247, Brooklyn, NY, December 09, 2013, 12:37
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I changed cabin filter still blows cold air what's next

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  • Answer #1

    chickenwing December 09, 2013, 13:16
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    Replace the thermostat, it is probably stuck in the closed position.

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    Seanluv247, December 09, 2013, 17:26
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    Where is thermostat

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  • Answer #2

    Greg's Orange Auto (12984 Answers) , Orange, CA - (714) 361-9386
    globalhelper December 09, 2013, 13:22
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    could be blend door stuck open

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    chickenwing, December 09, 2013, 15:42
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    What is a blend door???

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    ziptie12, December 09, 2013, 17:44
     Master

    It's a door inside the HVAC housing that controls the airflow through the heater core and A/C evaporator , to regulate air temp. Cabin filter - filters air. Stuck closed thermostat would cause overheating. CHECK coolant level first , and make sure the engine is reaching proper operating temp.

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