Heater fan and temperature control settings not working

[Rush Holladay]

I just traded my son a 2008 F150 for his 2003 TJ Sport. I may or may not keep it, but while I decide it needs a few things.

Functionally I need heat. While driving I get some heat through the main vents, but I think somehow that is engine heat that is getting blown into the cab when at speed.

When I move the fan selector, nothing happens. No air, no noise, nothing. When I move the temperature selector it gets colder or warmer.

When I click through the AC selections nothing happens. Even when I get to the non AC choices nothing happens either.

I don’t have any experience with repairs so please bear with me. Any step by step suggestions, links, Videos or other resources appreciated.

I’ve read enough to know the control switch, actuator doors and a $20-ish dollar electrical part may be the problem. My question - how to know where to start?

 

[05 Blue Unlimited]

I had a simular issue which turned out to be a vacuum line. Seems the PO changed the battery and crushed the vac line that runs between the bat and firewall. That is where I would start.

 

[Rush Holladay]

A vac line b/t the battery and firewall? I appreciate the help, but I just can’t make any sense of that. Would you tell me more?

 

[Chris]

Okay, so just so I'm tracking here, you're saying that when you turn on the fan, it doesn't work on settings 1-2-3-4? And you're also saying when you turn the knob that controls where the air blows out (i.e. face, feet, etc.), that doesn't change the direction of the airflow either?

 

[Eddie Greenlee]

When I move the fan selector, nothing happens. No air, no noise, nothing.

Im sure you have already checked the fuses ??

 

[Rush Holladay]

Okay, so just so I'm tracking here, you're saying that when you turn on the fan, it doesn't work on settings 1-2-3-4? And you're also saying when you turn the knob that controls where the air blows out (i.e. face, feet, etc.), that doesn't change the direction of the airflow either?

Correct.

 

[Rush Holladay]

Im sure you have already checked the fuses ??

Umm...No, I haven't. Are their specific ones to check? From memory, it seems the fuse box is under the hood, correct?

 

[Chris]

Well, first and foremost check your fuses just to rule that out.

You can find the fuse box location(s) in the FSM as well as what fuses are what. You can download a free FSM here: Jeep Wrangler TJ Factory Service Manuals (FSM) & Technical Documentation

See if your fuses are good (there is a fuse box under the hood and under the dash) first and foremost.

 

[Jeepcj6]

Check the resistor in the blower housing. Take out the glove box and you should see it. I youtubed it and it showed the whole process.Not hard at all. Good luck

 

[Chris]

Here's how to replace the blower motor resistor FYI:

 

[Rush Holladay]

Check the resistor in the blower housing. Take out the glove box and you should see it. I youtubed it and it showed the whole process.Not hard at all. Good luck

OK - what's the best way to search for that on youtube user name, video title? Or can you share the link here?

 

[Rush Holladay]

Here's how to replace the blower motor resistor FYI:

Thanks! I assume this is part number 5066 552AA according to the parts list?

 

[Chris]

Thanks! I assume this is part number 5066 552AA according to the parts list?

Correct! You can get a new one for $10 with free shipping:
https://www.amazon.com/dp/B003YLMPPA/?tag=wranglerorg-20

 

[Jeepcj6]

10 bucks is awesome. Cost me 40 something from the stealership. But hey its working in all speeds now.

 

[Rush Holladay]

Update. Got the part from Oreillys and followed the video.

Now I have heat blowing on the floor only in the 1st position. Temp still changes, not sure I’m getting anything thru the main or defrost vents. So, I’ll be happy to at least have what I have.

Now the question is - what’s the next step to get fan positions 2-4 to work? After that we can work on getting air through the main vents and defrost unless we can do all that at once.

Thanks for the help so far.

Much appreciated!

 

[Jeepcj6]

Hate to say this, mine worked on all positions when I replaced it. Did your old one look OK? Mine was bubbled in a couple of places. Might have to open up your HVAC control centre and jumper the plug in connector for the fan switch. Just a thought
Also just remembered to get my fan to work I had to turn the actual heater control switch to any position but all the way to the left.
Hope this helps

 

[KenR955]

Rush,
FWIW, If the fan only blows on high, and not on 1,2 or 3, the resistor is the issue most every time. I know that was not your issue, but stay with me now. If the fan does not blow at all, the fan motor itself is toast, the resistor is also toast, a fuse blew or a wire disconnected somewhere. If you disconnect the fan motor from the electrical connector, and you add power and ground to the two connectors with jumper wires, does the fan motor spin like crazy? If not, the motor is most likely toast. It might only work enough to spin on low. If it spins super fast,that means it works. Is it POSSIBLE then, that the new resistor is not working properly? Perhaps the speed switch is the culprit instead. Make sure the blower motor works when directly wired first tho, otherwise you can chase your tail for a long time.

 

[Eddie Greenlee]

the problem I can hear my fan is blowing its ( Fan off ), but it does not come out of the vent half as fast as the fan seems to be blowing. if i put it on floor setting it will come out front vents too.
are you having that problem too?

 

[Chris]

the problem I can hear my fan is blowing its ( Fan off ), but it does not come out of the vent half as fast as the fan seems to be blowing. if i put it on floor setting it will come out front vents too.
are you having that problem too?

It's highly possible your fan could be wearing out. With the age of these vehicles, it might actually be a good idea to replace the fan blower motor entirely.

 

[Eddie Greenlee]

replace the fan blower motor entirely.

aren't there doors inside the duct that open and close as you move the controls from foot to face to defrost? could those be messed up or would that have more to do with the vacuum lines?