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Rear Heat Problems

1K views 2 replies 3 participants last post by  roferg69 
#1 ·
Does anyone know where the rear blend door is located? I have a 04 passgr astro. My rear heat only blows cold, so I wanted to check to see if it had anything to do with the blend door.

Also, sometimes when I turn the front air/heat on high, the front blower motor makes a really annoying loud whirring/whining sound. Anybody know what this is?
 
#2 ·
There is no rear heat blend door. It is either on or off. When you turn on the rear heat two things are supposed to happen. The fan starts, and coolant begins to circulate through your rear heater core. If you are blowing cold back there, either your heater core is blocked due to excessive sediment in your antifreeze, or there is a problem with the coolant valve for rear heat. It is just under and behind your main heater control valve. It is all pretty easy to see when you remove your air cleaner. If your coolant looks normal and you have plenty of front heat, it is probably not the heater core. I would look at that valve. Check your vacuum lines.
 
#3 ·
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