Q: Overheats When Blowing Warm With Heat & AC But Not When Blowing Cold AC

asked by on January 22, 2017

2006 Mercury Mountaineer overheating when heater or AC blowing hot air. When the heat is on it starts to overheat. Once I turn the heat completely off, it cools back down. I turned on the AC and it was fine. Then, with the AC on I turned the temperature up to 90. It blowed the hot air but then started to overheat. When the AC is on and set to blow cold air, it's fine. So, it's only happening when the temp is turned up to get heat whether it's in heat mode or AC mode. Any ideas?
Autozone pulled these codes... P0446 P0196 P0506 P2004 P2005

My car has 153000 miles.
My car has an automatic transmission.

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