I have a 2014 F150 Platinum...125k miles...today...I discovered when I turn off the HVAC system...it keeps running. If its on Heat...it still blows hot...if its on cool...it still blows cool. Lights on the HVAC on the dash go on and off...but the system won't shut off.

Any ideas?

 

Have you disconnected the battery to try and reset any anomalies?

 

Nope... I try that.

 

My 14 did that…. It was the blower resistor.

 

Try what digitaltrucker mentioned just to see if that works for you. Otherwise i'm thinking Straight6jeff may be right. Do you have all of your fan speeds still?

 

Battery disconnect did not do the trick. Also noticed fan speed adjustment doesnt work.

Upon further research...seems likely the blower resistor as mentioned above. Gonna order am oem replacement and give it a go.

Thanks to all!

 

That's a pretty common sign of resistor failure. They're fairly easy to swap too just be careful when tightening those screws back into the plastic. They're easy to strip. May also want to check the plug and harness for any signs of melting or burning as that can happen also on these trucks.

 

Use OEM Motorcraft replacement only.
I know for a fact the Duralast won't work.

 

Just an FYI...I replaced the blower resistor...problem fixed.

$50 and about 20 minutes...wala!

Thanks to all that responded.