My wife drives a 2007 Sonata. Just recently the AC and heat stopped blowing air at all. I recharged the low side with r134a. My wife said that sometimes when she hits bumps it will come on for a little bit, but will go out often, and is not working more than it is. We live in south Mississippi so I need this problem fixed asap.

 

Let's hope you didn't overcharge the A/C system by adding addl refrigerant. If you did, it can cause other problems. What you might try , check the fuse for the blower motor and any plugs that go to the switch and the blower motor itself. It does sound like there is just a loose connection. Some systems also use a blower motor relay. You could look in your owner's manual and it should tell which fuse and it's location.

 

I changed the fuses for the blower and the ac and nothing changed. Any other suggestions? I know diagnosing ac problems can be a tricky situation. I just hope it is a problem I can fix myself without having to shell out a bunch of money.

 

By moving the fuse connection around you eliminated the possibility of a poor connection there.
Don't know if your vehicle has an automatic temp control for the A/C system or is a manual system.
What you might try is to tap things like the switches , the wires and the blower motor itself with the system on and calling for A/C. You might get lucky and come across the area where the problem lies.

 

It is the manual ac. I will try that I hope something works.

 

Is the A/C not working or is it just that the blower isn't blowing the air through the system? Maybe the A/C is fine but the blower doesn't work. Is the compressor running?

 

I fixed it. It was not blowing air at all. I pulled the cabin filter and it obviously had never been changed. When I pulled the filter out to change it, I manually started the blower motor with my hand and it kicked on. After the next few times of starting the car I had to manually start it again with my hand, but now it kicks on as soon as I start the car.

 

Can confirm - in 2022 - this works like a charm

 

How did you manually start the motor?

 

If you open up the glovebox and release its tabs so it can open all the way, you can remove the filter. Once the filter is removed, you get your hand into the blower unit. With your car running and your blower switched on, give the blower fan a spin. Imagine you're starting a propeller plane; one you manually get the blades spinning, there's a chance it will activate the blower to continue running. Obviously be cautious when doing this. Once that blower starts going, you'll want to pull your hand out quickly. This is probably far from advisable, but hey.. it worked.

I will say, though, this hack only worked for about a month. It stopped working for me, and I eventually had to cave for an actual repair through Hyundai. This cost around $900. The issue ended up being the blower adjustment **** itself...the only way to fix this was to replace the entire AC/Heat control assembly of the main control panel.

Best of luck