My dad has a 2013 Lancer and it has no A/C. Blowing warm air. I do not have a high end scanner but it did pick up a code as shown here: code (B1079) and most common fixes says "Replaced A/C Refrigerant Pressure Sensor" but does not tell me high or low? Any ideas? Also where are these located on the 2013 model, I am guessing it is somewhere if you follow the high and low lines but I have no idea what sensor to even start with because it did not say high or low. Any help would be great! Thanks for your time.

 

Tldr man im so ashamed from writing you a frekin poem about ac refill. I might be there and hold your hand while you do it 😂. Btw I registered for you specially 😂

1 Ignore cleaning any dtc with cheap tools they do dmg.
2 You have low pressure problem if no cold air comes when ac is on.
3. Read how to diagnose my pathetically extremely detailed info on damage to the AC system below.

B1079 when scanned should show as coolant leak. This means that the coolant might have leaked or simply due to age it has fallen low. Ac systsms leak at the compressor unit by design extremely slowly so it can lubricate the seals. If it doesn't blow cool air 90% of the time you dont have coolant pressure in the system. The other 10% is from damaged ac unit or leaking one or ac fan not working properly/spinning or at all. If the car has sustained any sort of frontal damage it might be a damaged radiator. Check when the DTC occured(mileage) and compare to current one. But I would ignore it all together. After all a faulty sensor wont affect your ac not blowing cool. Steps I would take if the car wasn't previously damaged is refill the coolant. If you're DIY-ing: There are 2 coolant options r1234yf and r134a. I think that all cars after 2016 use r1234yf so your car most likely uses r134a to be sure look for a sticker stating either of those under your bonnet. After you identify it go on Amazon and buy a r134a refill kit which has a hose with gauge. While you're there try to identify a pipe With a plastic cap with written "L" on it. Thats your low pressure maintenance port for the AC. There is also a "H" one that pipe will be thinner and you don't want to be anywhere close to touching that if you dont understand it for a simple refill you also wont need it. You will be using that to refill coolant in the system from the "L" port. Also don't worry even if you magically **** up and decide to suicide the port of the high pressure wont clamp. When the kit arrives screw the bottle to your hose. Make sure its fully closed before screwing hose to bottle. After that connect other end of hose to your low maintenance port it should click in. Make sure you're not pressing too hard on the pipe by supporting it from underneath with your other hand. After it clicks it will read something high. That's good it means you're connected to the system. Now go start the car set the ac to blow on the lowest possible temperature on the vents that are blowing against you and open them fully. Go back to your refill kit it should show close to 0psi now. Hold the bottle in a downward position and slowly open the valve. Don't panic the bottle might feel a bit stiff/huss that's normal. Watch the gauge don't fill too fast you don't want to overfill the system. It should take around 1-2m to top up natural loss of coolant. In that case you're most likely good. Make sure that the ac in your car is blowing cold air now. Save remaining coolant for other top ups. After finishing you cant remove the hose from the bottle or it will leak the coolant. Around 3+min to completely fill it but it might also you being too cautious and doing it way too slow. Either way mind where you fill the gauge up to. Give the car an hour after refilling and check the gauge while the ac is on again. If it dropped significantly you have a major leak that costs £££. If after a day it dropped slightly you have a minor leak. It can be fixed diy cheap by injecting leak sealant. If you have to completely fill you 100% have a leak tho. Also make sure not to fill higher than 55psi. Although you can just follow the green/blue red yellow on your gauge. I forgot about that DTC well you should too. In some cases you can screw something from not using a proper diagnostic tool and cleaning dtc. I wont recommend to clean it and it wont affect anything to be honest. I have a MTU-III at the shop and autel 808 at home. Both will do professional job at cleaning and reading dtc properly but don't recommend if youre not a professional(mtu3) or skilled diyer(autel). But your problem is 100% low pressure of the coolant. The refill kit is around 40-50£

 

The car was in a front end wreck, on the pass side too and I had the radiator replaced. The air worked fine before the accident but now it is not. The guy who did the work said he had no idea why the air was not working. I have not taken a real good look at the compressor or the wiring yet so as you mentioned we could have a broken line or connector. I was just thrown off by the error code. Thanks for the reply man it was a good read and a lot of good info.

 

What you need is a ac refill. If the radiator has been replaced then you can be 100% sure that there is no r134a which is in a gas form. If the guy that did the repair refilled afterwards you might have a leak from improperly done job. The question is did he refill itm did he add oil to the system to compensate for the loss. You should ask about the oil because while the radiator is disconnected you can just pour it in. There is also another issue which is that you now need a vaccum to be pulled on the system. Since there has been air introduced and air is humidit it meaning water in the system. Which is why the vaccum is needed otherwise the system wont be working at its maximum capacity. You can take it to someone who does ac refills/work. Ask around a bit before going to someone. Because there are tons of people that don't know what they are doing or are just ripping off people. Ripping off like not adding enough sealant so that you will need an ac recharge next summer. And you will go to him because last summer he fixed your ac and it was working right 😂. That's how some people think and I understand it. Still for DIY-ing because the radiator has been replaced you will also need to introduce a bit of ac oil since the system has lost some. Otherwise you might have to change the ac compressor a few hears down the line. If you want to save money instead of going to mechanic which is the way I recommend you can try getting an ac refill kit which has sealant and or oil in it like this one. https://amzn.eu/d/09SQGOzy. First you use up the bottle with r134a AND sealant and fill as much as you can. Then top up with the r134a refrigerant. That way your ac will still work and cool albeit around 90% performance without the vaccum pull. If you find a kit with oil in it even better although it still wont be enough oil in it for a radiator and the amount that probably dripped from the hoses. There are some tools you can buy to pour oil on dry system but tool for £40 oil for £10 refill kit with sealant £50. Still you will save around £100 DIY-ing. But the oil isn't extremely mandatory.