Skip the auto shop - Our mechanics make house calls

Q: Heater and fan not working

asked by on

The heater is not working and the fan only blows air on high.

A: Hello. There are several things that could ...

Hello. There are several things that could cause that heater to not work properly and the fan to only blow air on high. It is possible that you have a bad thermostat, which would cause the lack of heat. It is also possible that your heater control valve could be malfunctioning or that your heater core is going bad or is clogged. The most likely cause for the blower fan only blowing on high is that the blower motor resistor is malfunctioning. To determine the proper fix for your truck, a certified technician, such as one from YourMechanic, should diagnose your heater issue and make a recommendation for proper repairs to get your heater and fan working properly again.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Service light on, high temperature, heat off

The only way to gain insight as to what happened it to retrieve the diagnostic trouble codes associated with the Check Engine Light. Even if the Check Engine Light is not on anymore, you may be able to retrieve history...

Q: My transmision won't go into reverse, or D, and it doesn´t have neutral.

Hello. From what you describe it would appear that your transmission may have a serious issue. There are shift solenoids and pressure switches that can cause issues with shifting, however the symptoms you describe, along with the brown fluid, may...

Q: How many belts on a 2004 lincoln aviator. And if replaced still hearing a clicking noise what is the problem

Hi there. There is only one belt on the engine to drive all of the accessories. The clicking sound could be an accessory pulley out of alignment or a bearing in the accessory going out. The belt will make a...

Related articles

How Long Does a Distributor O Ring Last?
The distributor is part of the ignition system in your vehicle and its purpose is to route high voltage from the ignition coil to the spark plug. The spark plug then...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...