I believe that mine was leaking right from the factory, but it was such a small leak that it;s taken a couple of years to all leak out. In any event my Honda dealer has document that all the coolant had leaked out and that they were unable to find the leak - while it was under warranty. That's all I need to take it back at some future date, on or off warranty. I may actually just fix it myself since any visit to Honda ruins my day.

Most likely you see a bunch of UV Dye there because the UV Dye was added to the AC system through the low side service port. .
The plastic caps probably have a rubber gasket inside it which is intended to contain minor seepage from the schrader valve, so make sure the 2 caps are installed and snug.

Yes, I was expecting to see some dye on the Schrader valve where the coolant/dye was added. However it seemed to me when I checked a couple weeks later that the dye buildup had slightly increased, indicative of a leak. The plastic caps do not have a gasket of any kind. Their only purpose is to keep dirt out of the Schrader valve as far as I can tell. Nonetheless being plastic with tight fit, I noticed that when I removed the one it made a very slight hissing noise indicating a pressurized gas buildup being released. There should have been no leak whatsoever from a properly working Schrader valve. The fact that there was and it was slightly pressurizing the plastic cap just confirms a leak. My observations are somewhat subjective so:

I removed the plastic cap and took a small balloon, squeezed all the air out and snapped it over the Schrader valve. So initially it was lying there on it's side but when I looked at it a couple weeks later it was now upright and squeezing it I could feel that it was slightly pressurized. There is no doubt that there is a very slight leak from the Schrader valve.







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Anyone have the charts for (1) vent temperature verses blower intake temperature and humidity and (2) low side and high side pressure vs blower intake temperature and humidity? If you don't have these it is very easy to underfill or overfill. Without the charts the recommended method is to let out all the refrigerant (using a very expensive recovery machine, to keep bottle up and able to be re-used, rather than vented to the atmosphere) and then to put 15 ounces of refrigerant in. You just buy an 18 ounce can, weigh it, and use all but 3 ounces. Make sure it weights 15 ounces less than it did when you first weighed it. No more, no less.

Without the charts one would have to use the empty and refill method, which is a lot more expensive because you have to pay someone to recover the refrigerant.

If you refill right away, or within a few days, after letting out the old refrigerant, my understanding is you don't have to evacuate the system, and you don't have to replace the receiver dryer. Am I correct?

any luck identifying which is which relay?

I saw a gasket inside each plastic caps. I know they work because I have a sniffer, and if I sniff around the valves with the caps on, I don't hear the tell-tale speeded-up beeping that means it smells refrigerant. If I take off a cap, I'll hear a the beeps speeding up for about 10 seconds before they go back down to baseline speed, indicating that a very small amount of refrigerant escaped from the valve, and and had been held in by the cap. If I put the cap back on, and check a few minutes later – no leak detected. However if I leave the cap on for a month before removing it, the sniffer will pick up some refrigerant that leaked out from the valve and had up until then been held in by the cap. I don't remember if it was the hi or the lo side valve that leaked, I think both.

Sometimes a schrader valve get's sticky, and leaks a bit. If that is the case, sometimes you can unstick it by briefly pressing on the pin to let out a bit of refrigerant. As the pin pops back up from the pressure, it may close more tightly than previously.

I found this diagram showing where the AC compressor clutch relay is. I hope it's accurate. I haven't checked it out yet. Usually relay has smaller spade connectors for the low current controlling side, and larger connectors for the controlled side, the fatter wire, larger current side that provides power to the component.

It is from "Auto Repair Source Motor Driven," repair manual available on line with my library card, Buncombe County NC. HVAC wiring diagram from same source shows that jumping terminals 17 to 18 brings power to the AC clutch. But use your own judgement. I can make mistakes and I don't' accept responsibility for damage if you jump 17 to 18 and something bad happens! Also, I haven't tried jumping them yet and I don't know if ARSMD accepts responsibility for the accuracy of their info!

Let me know if you want the wiring diagram. I can upload that also if you want it.

https://cimg5.ibsrv.net/gimg/www.fit...c76246a502.gif

Jeez I tried to remove the relay but I couldn't get a grip on it with my fingers. Anyone have any ideas how to get it out with first breaking it into pieces?

Yes I managed to get the relay out. I used a channel lock plier. I adjusted it's opening size in order to avoid putting too much pressure on the case when grasping it. Although I'm afraid I made a very slight dent on one side anyway. Barely more than a scratch. The relay still works though. OEM versions of those things are amazingly expensive. Like $45 US or so. I'm going to pick up relay puller at O'Reilly's, overpriced at. $23 but I can't wait until the end of August in order to get one for $13 on ebay.

I uploaded the wiring diagram for the HVAC system, heating and cooling. Can anyone tell me if there is a way to determine the wire gauge of each wire. For example all the way at the upper left is the battery and the battery terminal fuse box. A wire coming from it goes to the "underhood fusebox" where it goes through a 7.5 amp fuse labeled B14, and then at connector 77, out comes a wire labeled |EA| PUR. I'm guessing that PUR means purple because in the diagram the wire is colored purple. But what does |EA| mean? The purple wire, after going to something labeled C202 and 15, continues on to terminal 17 of the AC compressor clutch relay. Then out from the relay at terminal 18 comes a wire labeled |EL| pink. I'm guessing this wire is pink. At connector C201 13 out comes a wire labeled |EC| BRN. I'm guessing BRN must mean brown. But what does |EC| mean, And most important: what is the wire gauge of these wires? It would be nice to know, before I crimp spade connectors onto the end of a wire, to make a jumper for terminals 17 to 18. I want to have this ready just in case I need to turn on the compresser this way, when filling the system with 15 oz (425 grams) of refrigerant, from an empty system. .

Edit: unfortunately fitfreak's message board software shrunk the image. The image I uploaded 968 kb 4800 by 2687 pixels, but the image being displayed by the discussion board is 97 kb.and 1299 by 727 pixels. What I can do when I get a chance is upload the image to my web site and provide a link.


https://cimg8.ibsrv.net/gimg/www.fit...5bdf378c7f.jpg

I'm not sure - it is barely legible on my end after downloading. Thank you for sharing. Not sure on gauge but with 12V DC (rem: 12V thus carries higher current than home 120V due to the lower V potential) the recommended wiring size is shown below:
https://cimg9.ibsrv.net/gimg/www.fit...ac9a7964ce.png

Thanks for the chart Jazu. I used a piece of 12 gauge stranded wire and crimped a spade connector onto each end. The shorter the length of the wire, the thinner wire you can use. The length of my jumper wire was only about 12 cm. It looks like the amperage of the fuse for the clutch relay is 7.5 amps, and there is nothing else on that fuse. I see from your chart that for 10 amps and 15 feet – or is that 15 meters, it's not clear – you need 12 gauge, so actually my wire, because it is much shorter, may be a little thicker than it needed to be, which is fine. For a 12 cm piece of wire, being used for only a few seconds, probably 14 or 16 would have been fine. When I jumped the relay for a few seconds the wire didn't get the least bit warm.

I wish I knew how to get the full wiring diagram with all its pixels to be displayed on fitfreak.

OK, I tested the jumper and it worked. It didn't get at all warm, But I didn't need the jumper. I just attached a full 12 ounce can of 134a to the system, at the low side port, and as soon as a little bit of it went from the can to the system, the compressor started right up.

How did my system get to be nearly empty? I was trying to top off the system, using a gauge set, and reading ambient temp and humidity, low side pressure, high side pressure, and vent temperature. Because the brand new adapter for the high side port was leaking, refrigerant going into the low side port was coming out the high side port faster than it was going into the low side port. I took apart the adapter and saw that one of the 2 tiny o-rings inside was broken. By time I realized what was going on (this was the first time I had tried to charge a system), the AC system had become nearly empty. Some refrigerant oil was lost too. So now I want to add some oil to make up for the lost oil, though I'm not sure how much was lost. I ordered new adapters but meanwhile I charged the system by emptying it completely and adding a full 15 oz of refrigerant through the low side. High side was not hooked up to the gauge set at all but didn't need to see the high side pressure because I charged the empty system with a weighed amount of refrigerant, one 12 ounce can, and 3 ounces from a second can. I bought a gram scale and measured the amount of refrigerant in the can, and confirmed that after being used it weighed 3 ounces less than it weighed before being used. The vent temperature is now a little bit cooler than it was before I began working on it. On an 85 degree day with 60% relative humidity, before refilling the system I was seeing 43-44 deg F at the vent, at its lowest temperature, after driving 15 miles.. Now I'm seeing 40-41. Even 39.5 occasionally. But the car is still not comfortably cool in 90 degree, sunny weather. If it's 90 degrees and cloudy the AC can keep up. If its 90 deg and sunny, the AC cannot keep up. Radiant heat coming in through the windows heats the car up as fast as the AC cools it down. Cabin temp won't go below about 80 deg F. If sun is on the driver's side I blow air from the vents directly onto my face, but I still I feel the hot sun on the left side of my face, causing discomfort. It takes about 15 miles of driving for the cabin to get down to as far as it will go.

Does anyone know of dongle that will report AC data trouble codes for the 2015 fit? Preferably one that works with a Windows 10 computer as I hate looking at a tiny Android op sys smart phone screen with fingerprints on it. A big laptop screen is much easier to use. Connection by bluetooth preferable, but usb would also be ok. I like to leave wifi open for connecting the computer to the internet via wifi.

I'd like to recover the refrigerant and recharge the system, this time evacuating before refilling, Perhaps I can get a bit lower temperatures, if I get some moisture out of the system but I have no place where I can work on the car, where I can plug in my vacuum pump. I bought the car new and never removed any parts from the AC system. It has never been left without refrigerant in it for more than a few hours, so there shouldn't be much moisture in the system. But who knows. Maybe it was never properly evacuated at the factory. Maybe one of the sensors is reading wrong. AC Data Trouble Codes should tell me if that is so, once I buy a scanner dongle that reads Honda AC codes, if I can find one that is affordable. My current dongle reads only engine codes.

Normal! If the car is painted a dark color, it's even worse.
The AC system is simply undersized, not much you can do about that.
Your hvac control panel is 3 round knobs, a lever, and push-pull cables, right? AFAIK there is only basic ac data available and would be found in the PCM data list. Probably limited to ac request y/n, compressor and fan relay commands, and ac system high side pressure sensor value, if your chosen scanner even supports that much data.

Yes the system should be evacuated before charging.
Not only to boil out any residual moisture that could have entered while the system was open, but also to extract all traces of air from the system before charging.
Air in an ac system reduces cooling performance.
Moisture inside a system typically shows up as causing refrigerant flow blockage at the expansion valve whenever the moisture decides to freeze.

When I check my AC pressure, hi and low, after leaving the car parked for an hour, they are close to the same pressure, about 95 low 100 high, however if I run the AC for 10 minutes, allow the low pressure to go below 50 and the high above 200, and then shut it off, it takes a rather long time for the pressures to equalize. At least 30 minutes. I'm wondering if there is something wrong with the expansion valve. If I recall correctly it should have a device to measure temperatures and close up the size of the expansion valve ofrifice when the temp gets of the evaporator gets too low, to prevent it from icing. But I'm wondering if maybe that temp is set too high. In 75 deg F weather, with the engine going at 1500 rpm,I never see the temp out of the vent go below 40 deg F. It usually stays between 43 and 50. Even higher wtih the engine at idle, like between 47 and 55.

The wiring diagram I posted above shows that the car has an "evaporator temperature sensor" with wires going to it so some scan tools that show hvac info might be able to tell me the temperature measured by the evaporator temperature, just like they tell me the temperature measured by the ECT sensor, the Engine Coolant Temperature sensor. Perhaps the ECU might even produce a data trouble code if the evaporator temperature sensor is not functioning correctly, and is decreasing the orifice or shutting off the expansion valve, before the temperature gets as low as it should get, for that to happen..