Heater blows either Hot or Cold, but nothing in between.

[FishCannon]

Help!

A weird thing started happening. 2012 P4X, 102k miles. If I turn the heat up all the way, it will blow hot air, but if I turn it down even one notch, it blows cold. It's like there's no mixing of hot and cold air to make a comfortable temp. When it's blowing cold, if I turn the heat up one notch at a time nothing happens until I get to the last notch, then it starts blowing hot.

Coolant level is good in both the radiator and the reservoir. It's the Nissan blue stuff, and I haven't found any leaks anywhere.

What could cause this?

 

[Brunnie]

Sounds like a blend door problem.

 

[Prime]

Definitely an issue with the blend door. If I get some time this week I'll dig through the FSM and see if I can find out what's up.

 

[FishCannon]

Yesterday I was able to get in there and do some tracking. When I turn the Temp Control Knob, I can hear the blend door actuator move slightly, but once in a while it sounds like it's getting stuck and keeps trying. Sounds almost like a small, stripped gear. I took a video with my phone, but it's too large of a file size to upload. Maybe tonight I'll take a shorter video and see if I can get that uploaded. For now though, I'll go ahead and order an actuator from nissanpartsdeal.com. That way I'll have it for when I'm ready to do the install.