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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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, Brooklyn, NY, December 09, 2013, 15:37
 Rookie

I changed cabin filter still blows cold air what's next

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  • Answer #1

    December 09, 2013, 16:16
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     Rookie

    Replace the thermostat, it is probably stuck in the closed position.

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    , December 09, 2013, 20:26
     Rookie

    Where is thermostat

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  • Answer #2

    Greg's Orange Auto (15380 Answers) , Orange, CA - (714) 361-9386
    globalhelper December 09, 2013, 16:22
     Master

    could be blend door stuck open

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    , December 09, 2013, 18:42
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     Rookie

    What is a blend door???

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    , December 09, 2013, 20:44
     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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