Heater not working

[Domking3465]

When I turn my heater on it blows ice cold air does anyone know what it could be.

 

[86GT351]

Could be the control unit or possibly an actuator. Do all the other functions on the control panel work?

 

[Dino Dino Bambino]

When I turn my heater on it blows ice cold air does anyone know what it could be.

Firstly make sure the AC button is off.
If your engine warms up to normal operating temperature, that'll rule out a stuck open thermostat.
It's then more likely that either the gears inside the temperature blend door actuator (the lower of the two behind the center stack on the passenger side) is broken, or the blend door itself is stuck. Here's my guide on how to replace the actuator:

How To: Dash Blend Door Actuator Replacement 05-09 Mustang

In total there are four: 1. Floor/dash vent actuator on driver's side behind gauge cluster (Motorcraft part no. YH 1870). 2. Defrost vent actuator on passenger side behind the center console (upper) (Motorcraft part no. YH 1870). 3. Temperature blend door actuator on passenger side behind the...

www.s197forum.com

Luckily it's an easy sub-30 minute job if you lie with your head under the dash in the passenger side footwell and work with your left hand. Move the passenger seat all the way back. If you're of the tall, large-framed variety, removing the passenger seat altogether will make life much easier. You can do that in 10 minutes.

 

[Domking3465]

Yes all other functions work. I turn off the button and still Ice cold air. My temp switch feels loose is that normal?

 

[Domking3465]

Could be the control unit or possibly an actuator. Do all the other functions on the control panel work?

Yes the temp knob feel’s really loose is that normal

 

[Miker]

Mine is loose as in it feels like it isn't connected to any moving parts so zero resistance to turning it. I thought that it was weird but it does work as it should.

 

[Domking3465]

Mine is loose as in it feels like it isn't connected to any moving parts so zero resistance to turning it. I thought that it was weird but it does work as it should.

So that’s normal then? You’re temp still changes no matter where I turn it it’s ice cold air. Just a bummer I just bought the car

 

[wildlifeguy]

Just some of the things I have experienced over the years in my vehicles:
1. broken/cracked knob. The knob spins but is not turning the switch. I would think the knob would pull off easily if not grabbing the switch post. I had this happen in a 99 expedition with similar knob.
2. malfunctioning temp blend switch. I don't think this is likely with this type of switch.
3. malfunctioning actuator. In my opinion, this is the most likely cause of your issue. Maybe try with key in run position and engine off turning knob. You should be able to hear a faint hum if the actuator is moving. You can also remove the glove compartment, locate the correct actuator and hold it with one hand while turning the temp knob. If moving, you should feel some vibration and feel the lever that it is moving. It could be that it was clicking and the previous owner disconnected it to stop hearing the noise. To get better visibility, you can also remove the airbag in less than 5 minutes taking appropriate safety precautions.
4. broken blend door. Also happened to my expedition (dash removal). Air temp would change with braking and acceleration.
5. clogged heater core. I've had this happen in a couple of jeeps. However, I think you would at least get lukewarm air. Ensure that the heater hoses are connected at the firewall and engine; it's possible that the previous owner bypassed it. Both heater hoses should be very hot to the touch when the engine is at operating temp.

I'm sure there could be other causes, but this is what I have experienced in the past.

 

[Dino Dino Bambino]

You don't need to remove either the glovebox or the passenger side airbag to get to the temperature blend door actuator. Just empty the contents from the glovebox, push the sides in so the rubber snubbers can clear the dash, and allow the glovebox to drop to the floor. You then have plenty of room for your head as you lie on your back.

 

[Domking3465]

Just some of the things I have experienced over the years in my vehicles:
1. broken/cracked knob. The knob spins but is not turning the switch. I would think the knob would pull off easily if not grabbing the switch post. I had this happen in a 99 expedition with similar knob.
2. malfunctioning temp blend switch. I don't think this is likely with this type of switch.
3. malfunctioning actuator. In my opinion, this is the most likely cause of your issue. Maybe try with key in run position and engine off turning knob. You should be able to hear a faint hum if the actuator is moving. You can also remove the glove compartment, locate the correct actuator and hold it with one hand while turning the temp knob. If moving, you should feel some vibration and feel the lever that it is moving. It could be that it was clicking and the previous owner disconnected it to stop hearing the noise. To get better visibility, you can also remove the airbag in less than 5 minutes taking appropriate safety precautions.
4. broken blend door. Also happened to my expedition (dash removal). Air temp would change with braking and acceleration.
5. clogged heater core. I've had this happen in a couple of jeeps. However, I think you would at least get lukewarm air. Ensure that the heater hoses are connected at the firewall and engine; it's possible that the previous owner bypassed it. Both heater hoses should be very hot to the touch when the engine is at operating temp.

I'm sure there could be other causes, but this is what I have experienced in the past.

So it would be the actuator behind the stereo. One day it did get stuck on defrost only but when I went to work and came back it was working normal. So that part also affects the heat too.