Heater Blowing Cold Air

Trying to find the common thread that works heat. Last night switching into 4wd the 4lo just started blinking without engaging even 4hi. Only way to stop it from blinking was to restart vehicle. Now this morning the engine temp is good, blower working and no heat coming out.

what is the common thread that isn’t just my habit of beating on it hard?

thanks for ideas

 

That was the first thing

 

Question is what wire did a mouse chew or what fuse blew that knocks out heater and 4wd

 

Bump for ideas. Checked almost every fuse so far

 

You must work for Xfinity...

 

Heater started working again. Odd

 

Heater usually blows cold if there is a coolant bubble in the heater core not allowing it to circulate hot engine coolant. It also won't put out much heat until the engine is up to temp.

Sounds like you have some electrical issues on this thing tho man, might want to remove the electrical mods you have and/or get it checked out.

 

Bend door actuator is probably getting ready to go bad

 

I was starting to think the blend door as well. 09 did the same were it was difficult to get it to switch hot/cold or from defrost to anything else. Eventually just left it hot and on defrost. Rolled windows down in the summer and shut off fan.