2003 Galant NO interior heat.

Engine heats to operating temperature, air conditioning and fan work BUT NO heat in the interior. I understand that it may be a flap(?) not opening.

Advice please, what do I look for?

 

In the schematic for the Heating and Air Conditioning system electrical, there is a solenoid labeled "Water Shut Motor", this is likely to be the source of the problem. This solenoid actuates a valve that permits the flow of coolant into the heater core. If it is stuck closed, no coolant can get into the core, and you get no heat. The Haynes manual does not identify this part anywhere that I can find, other than on this schematic.

I think fuse 16 supports this solenoid, so check it first.

This link will show you where to find it.

https://www.justanswer.com/mitsubish...-actuator.html

Good luck.