Car heater electrics - wrx 2003 impreza

[Mike impreza]

Don’t know if anyone can help me. My car heater blower is getting no power until the car gets up to running temperature only then will it kick in. Once up to running temp it works great on all settings. I have changed relay, resistor and the motor but it’s still the same… any ideas?

 

[brianmoooore]

I run a BMW, slightly older than your car, and what you describe is almost normal behaviour. The heater won't push out much air until it ha some heat to push out, otherwise it would be blowing cold air at you in an already cold cabin. Having said that, the fan does run slowly with a cold engine, just ventilating the cabin, without causing a draught, so maybe it's that part that has failed on yours

 

[Mike impreza]

I run a BMW, slightly older than your car, and what you describe is almost normal behaviour. The heater won't push out much air until it ha some heat to push out, otherwise it would be blowing cold air at you in an already cold cabin. Having said that, the fan does run slowly with a cold engine, just ventilating the cabin, without causing a draught, so maybe it's that part that has failed on yours

Thanks Brian, I don’t think the Subaru is like this normally though, if u set full power on blower even when cold it should blow cold at full speed. Not good when it’s misting in this weather. I have to drive a mile before it will do anything.. just can’t get my head round it. All I can think to change now is the heater control cluster but I don’t see how the heat of the engine can affect the heater motor Power supply