My Air Conditioning No Longer Works

Well, if the AC is not working you won't be able to fix it yourself, so you'll need to eventually visit either your local Toyota dealer's service dept, or your 2nd cousin's husband, or someone else who is a Prius-trained tech.

If you want to gain some insight into the problem, warm up the engine first. Keep the car in READY, in P, set the parking brake firmly, and wait until the engine is no longer running. Then set the cabin air temp to MAX COLD (or LO, depending upon model year), turn on the A/C button on the MFD, open the hood, and see if you can hear the air conditioner compressor running. The compressor is visible with the hood open as you look down in the space between the engine and radiator, is mounted to the engine, has a silver cylindrical case, and has an orange high voltage cable from the inverter running to it.

If not running, then either the compressor, the inverter, or the AC ECU is bad.

If the compressor is running, then you can attempt to feel the low pressure tubing feeding the air conditioner (being careful not to injure yourself in the event that the engine or the radiator fan starts to run) to see whether it is cold after the compressor has been running a short while. You may also see water condensation form on the low pressure side, as water vapor in the air condenses.

If it is not cold, then the refrigerant is low. If you can find the sight glass and see bubbles in it, that is also evidence the refrigerant is low.

If the low pressure side is cold (which means the high pressure side will be very hot) then the air conditioning function should be working as long as the cabin air blower is operating.

 

My lifetime average is not much lower than yours and I run the car with ac non stop down here in Florida even in the winter so your not really saving anything by not running the ac.

And the other thing is not running the ac allows alot of humidity into the cabin. Cabin full of humidity and then you get out and that humidity sits in the cabin. That will make the car stink eventually as it will attack the fabric and carpet. Humidity is very hard on all the car's cabin electronics connections and plugs. And there's thousands of them in the Prius cabin. Every metal connection in the cabin will corrode eventually. This is not just a Prius thing its like that with all car's especially down here.

And thats hard on the traction battery connections that have had issues corroding. Plus you want to do all you can to keep the tracion battery cool.

Riding around with a hot humid cabin all year to save $50 a year is not good business.

Hardly ever using the ac is bad for the ac too. The compressor needs circulation once in a while for lubrication. Supposed to turn on the ac even in winter once in a while.

 

The Prius A/C condenser is vulnerable to road debris. It doesn't take much of a rock to put a tiny hole in the fin or header tank, and slowly lose your refrigerant

I fashioned a grille guard for my Prius after just one year, considering the road impact my condenser already had

First step is to check the A/C charge. The official Toyota Techinfo site, and All Data, has detailed diagnostics on what to do next

 

When the air conditioner quit working in my 2005 a couple of years ago the dealer determined the refrigerant was low. After recharging, no leak could be found. A dye was added to the system to assist in locating the leak later (It was supposed to stain that location.) The next couple of times I was having my oil changed the dealer checked but couldn't find the leak.

The AC was recharged and the dye was added about two years ago; the AC continues to perform normally. Go figure.

 

Good luck getting anything covered by warranty when there's any way they can blame you.

 

I replaced the condenser on my salvage car for about $125. Since your AC system is already empty you should not have to evacuate the system before you replace it. It's actually a quiet easy job.

 

If I were you I would recharge the system myself first and see what I've got. $1,000? F that...even if it has a leak you can recharge it yourself 30 times before you get to that number...as little as you use the A/C I wouldn't spend $1,000 on it...lordy...

Go to PepBoys or whatever autoparts chain you have locally and buy one of those "Recharge Kits" they're about $35 and they include a bottle of 134a refrigerant and a gauge. Follow the instructions on the bottle. The system has a low-pressure switch so it won't run the compressor if theres no refrigerant in the system to keep from wearing out the compressor. I bet you will find it has little or no refrigerant and once you empty one of those cans into the system it will work fine. If theres a leak then it won't work fine forever, but once you have the initial kit the additional cans of refrigerant are cheaper. Doesn't work? Add more refrigerant.

I just did it on our Explorer and its very easy...I don't know where the low pressure valve is on the Prius but I'm sure people here can tell you.

Toyota and Lexus dealers are all about "just replace any part that might cause the issue" and when you have an older car...you just can't afford to take that approach...

 

If you replace the refrigerant without the correct non-conductive oil it will destroy the compressor. The $1000 repair will become a $1500 repair.

 

I am a new Prius 2010 owner (almost two weeks). I am not familiar with all the ins and outs of a Prius yet.

From all the cars I have had in the past (non-hybrids), I know....have been told and been verified...that if you don't use the A/C, it can stop working. It could be Freon, could be the compressor, but it can stop working from non-use.

Rob.

 

Thats a really good point. Since the Prius' system is all electric you do need to make sure that the refrigerant you use contains the correct oil. I didn't think about that.

I don't know if such refrigerant is available locally or not...or if the dealer even sells it.

 

DON'T buy a "recharge kit" Most of those kits contain R143a that has seal conditioners and compressor oil in the cans of refrigerant. If you want to throw a can or two or R143a in just be sure that is does not contain any oil. R143a with no oil is readily available at any parts store. If you do replace the condenser you will have to add about a tablespoon of the special oil. Unfortunately it is about $125 a bottle (which just happens to be enough for 3 full oil fills) and is only available from Toyota. I have a 95% full can of the stuff just sitting on a shelf in my garage....

 

Tideland, by 'directly' ... are you thinking 'indirectly' ?? That's what I first thought about. Isn't the traction pack / cooling managed by the AC ? Not a problem necessarily at altitude or winter ... but the OP's from San Diego & inland SD temps get toasty in the summer.

Did I tell everyone how many times my extended warranty has paid for itself? Even on our hybrid Lexus SUV ... just a few weeks ago, an ECU was faulty. Whew! Just out of the 48month warranty, that repaid $700 of the $1,900 bumper to bumper extended warranty. They're a crap shoot ... just like any insurance.

 

HELP!!! My air conditioning stopped working as well on my 2008 Prius with only 26,000 miles! The dealer also said the condensor had a hole in it from some outside something-a rock?? and said it would cost $1,200 to repair- OUCH- how can this thing break so easily & is there anything to be done -get Toyota to repair??????
This is my first chat experience- please help!!!!

 

Patrick, would the inverter throw a code if it had a problem? I have no codes coming up when checked. If no code, should I replaced the AC ECU? (I just replaced my compressor and it doesn't start). My AC simply stopped working one day.

And exactly where is the AC ECU?

Thanks!

 

Yes

What are you using to retrieve the DTC?

No.

Why did you replace the AC compressor?

What does "stopped working" mean? For example, does the cabin ventilation fan run? Does the system produce heat?

The AC amplfier is located below an air duct, behind the trim panel that runs from the floor hump up to the instrument panel.