My Toyota AC is Not Blowing Cold Air

My 2012 Toyota Sienna AC is not blowing cold air. I go through the steps to check the freon levels as well as replace the flow sensor, which is a common problem in these Toyotas. Our Sienna has a 3.5L V6 engine.

AC repair can be very intimidating, but as long as you do not need to drain freon from the system, it's not very difficult. The flow sensor in the AC is hard to reach, but otherwise a very simple replacement Check out the link below for the part.

Attempt repairs at your own risk.

[richardroof]

Good info on that sensor. My wife's 2012 Camry wasn't cooling. I used a telescopic magnet while the car was running with a/c turned on and the second fan came on and a/c clutch engaged when I touched magnet around the top of sensor. I took a small refrigerator magnet holding some bs on the refrigerator door and stuck it on top of sensor (in particular the snap ring) and let it ride for now. Car is cooling, wife is happy, been about 4 months now, magnet still hanging on! One day I will install the sensor, just not today. Lol

[tangtran]

Just did it, it worked! Blowing 58F of cold air. 🥶Longest part was filing the tip down to fit the smaller hole, wiggling out the old sensor and putting the C clap back. I found an easy way to put the clap back by first with your hand place the small hole side in first and used one side of the c clap plier to push the big hole side in. After that used the piler to check if it is secure by pushing the clap in.
Thanks for the video tip, you saved me a new compressor.

[azmyeyes]

Thanks it works after changing A/C air flow sensor part cost $18

[johnnotorfrancesco]

I will try this Saturday, , I’m grateful to find your video, same van / yr… sounds promising

[matthewdo]

For this specific AC issue, if use the BlueDriver OBD scan tool you'll see DTC B1479 Flow sensor circuit.

[charlieyanez]

The sensor doesn’t come off that easy, it broke in place while trying to remove it. It seems to be glued in. Only option other than removing compressor is to break it and there is no room to work on 2015 Avalon.
Air conditioning works with flow sensor just plugged in without installing it in original spot. I will try to chisel old sensor out.

Beware if you are going to try replacing sensor.

Update: Tried removing the radiator fan assembly to have more room to access the sensor spot on compressor to chisel the old sensor out. Too complicated. I gave up before I broke something else.

[vincevancleave]

Reminder: The sensor is there to sense flow. If you get a code for flow sensing circuit, the first thing you should check is the refrigerant level.

[davidjaminsky]

It’s my understanding if this sensor is bad, your ac won’t cool at all. I plan on replacing it myself for intermittent cooling on my rav4. Also the compressors with this sensor generally aren’t electromagnetic clutch. The end on the compressor can be seen spinning while no refrigerant is being pumped. This also is my case. It had me confused when I saw the compressor spinning and nothing changed on my manifold gauges. 😂

[mltlawyer]

Nice Video. I changed my sensor flow following your instructions. But, my arms look like tree trunks that were shredded by bears.

[MikeSiemens]

While you went through a number of procedures, how can you determine if replacing the sensor had anything to do with the fix? I don't see how replacing a flow sensor would change anything in the performance of the AC. I suspect the improvement in cooling may have been hooking up the recharge bottle. One other point, looking at the front of the compressor to determine whether it is spinning or not means nothing. The pulley spins all the time as it's integral to the belt system. What causes the actual compressor to spin is the engagement of the magnetic clutch on the front of the unit.

[RxRau-kgot]

I used the same gauge that comes with the refrigerant, and it has worked many times. If however i have a more serious problem, I'd go to a friend who has a real set of gauges

[alexwill]

I've watched a couple other videos on Youtube and I have to say that yours is the clearest info and no extra fluff to make it a 15 minute watch. I appreciate that. I have a question though. I think ( watched it twice ) you said that Toyota doesn't sell this part? The AC on my 2017 Highlander was "looked over" at the dealership 2 years ago ( off warranty by then ) and the mechanic checked everything like you did and finally put in a little R134a and a sealer / dye because he said he suspected a very small leak. Everything worked fine until this Spring when the AC started blowing "cool" air that can't keep up if the temperature outside hits around 80 plus. 2 years go it cost me just under $200 to have that work done so I suspect it's $300 or more now. With a 5 + year old vehicle I would think this sensor is likely the culprit or should be replaced anyways and sounds like Toyota dealerships don't want to do that and or replace that $30???? part instead of charging over $1000 to do th whole compressor. By the way other than the question about the part being available from Toyota, how is your replacement holding up since it's ben around a year?

[ginarperez]

Thanks for the tip on checking the sensor.
PS. Maybe a laser pointer will help point out parts in future videos. ;)

[mediacreationsusa]

I would start with a set of gauges - the low side is only half the story... plus a can gauge is not gonna be accurate - need to see the high side too. BTW that alt connection is not a ground, that is the "always hot" from the battery... the ground is gotten by the bolts to the engine... another note - the compressor is always spinning... what you are talking about is the clutch engaging or not... another way to tell if you are low on 134 is if it cycles a lot... you can't miss the sound of it engaging... if it stays engaged, chances are it's not low...

[mike-ypuk]

That flow sensor is an rpm signal which the computer uses to determine the status for clutch engagement. It needs a clean surface underneath before you install it as the strength of the magnetic field is effected by air gap. You can actually see the rpm signal on a professional scanner. One hour replacement time is not bad. Lol the real problem is when you add an improper amount of refrigerant this raises the high pressure and results in bad compression ratio. Can damage the compressor and give poor gas mileage. Those cans cause trouble as well as help. It's like a gun in the wrong hands. Lol if your engine vibrates on hot summer days turn the ac off and it gets better you will know. Lmao dorman is a very cheap Chinese brand so good luck with it but the cost makes it worth it. Don't be surprised if you have to do it again. Lol

[nordicpride]

Good video. I will say a temperature/pressure chart that accounts for humidity is definitely necessary having rebuilt countless R-134a systems. Also a manifold gauge set is many times more accurate than that shitty offshore gauge that’s on a can. Just go to HF and get a $65 manifold gauge kit. Modern AC systems are very picky about pressure. If you overfill it won’t cool adequately, and you will eventually fry your compressor. Other than that great info for people who are unaware of this sensor.

[keithnoneya]

Nice video Raider. On the battery terminal, poor any soda pop on it, no joke, the carbonized water will eat the corrosion and then you can rinse it off with a garden hose. You can either air dry it or drive the car for 20 minutes, then you can put some CRC 05046 Battery Terminal Protector on it to slow further corrosion. Unfortunately the shops have to charge that much money to cover their shop overhead, of which us driveway mechanics don't have. My dad ran a mechanics shop and one of the biggest problems obviously was Rent, Utilities, Insurance and a huge portion of the bills were TAXES and Government Fees, then if he made any money he had to pay his income tax. We BARELY were able to afford an FH Home, Government Subsidized Home in Idaho. We shopped at the goodwill for clothes. Thanks for sharing. Best Wishes & Blessings. Keith Noneya

[RxRau-kgot]

What if you removed the radiator fan housing to get more room?

[omarcorrea]

When your mechanic recommended replacing the compressor did they tell you what the pressure was reading on the high and low?

[marioxzbp]

What about if i try the magnet but still doing nothing, everything its brand nee