CLK430

Does anyone know where I can add refrigerant to my car? My A/C is blowing warm air now. I tried looking in our manuals and found only the spec of the refrigerant. Could someone plz describe the area that I'm looking for? Also, is this refrigerant hard to find at pep boys? Thanks all!

CARLSS0N

I think is better for you to go to a shop to charge refrigerant, I think any shop will do a good job but if you are planning to do it on your own then you will need to buy the regulator for it, if not you might break some of seals
Yes, pep boys , kragen, autozone will have refrigerant and be sure to buy R134 not R12

Bagher

this is not a DIY job. go to a shop.

RED-CLK

First of all see if the electrical clutch in the front of the compressor is energized so the actual AC compressor is working /turning. If it is, a set of guages need to be hooked up to see if the system pressures are correct or not. If you just add a can of freon and the system didn't need it because that might not be the problem, you WILL do more harm than good to the Ac system. By you just asking this question, leads me to believe you need to go to an repair shop, it doesn't have to be the stealership.

newspeed

you can totally do it yourself... dont listen to the take it to the shop crap... No offense guys but this forum is filled with a bunch of people who dont do anything to their cars except driving it to the service centers... Go to any bmw forums and people are always trying to help each other out and figuring out how to do things themselves..

Anyway, i had a similar problem..warm air and the a/c compressor would not turn on. If the system is low on freon the compressor will not turn on by default to prevent damage. You need to go to autozone or anyother place and by the regulator gauges with both the low and high side pressures.

On the clk, the low side connection is on the drivers side of the engine around the middle next to the spark plugs on that side.. Look for an aluminum tube with a plastic screw cap on it. Remove the black cap and its ready to connect the low side hose to it..

Now the high side is where the grill is on the front of the car also on the drivers side.. Look carefully behind the black plastic inner grill and youll see it.. same screw cap, take it off and plug the high side hose on there.

Now start up the car and turn the ac on the coldest setting.. (make sure the ec button is not on) Open up the valves on the regulator and read how much freon is in there.. the gauges will tell you if there is enough, too low, or too high...

In my case i was very low on freon so i added a can until the gauges read in the proper pressures and sure enough the compressor clicked on and after 3-4 minutes of running i started to get cold air.. Its been almost a week now and im still getting ice cold air.... Worked like a charm and only cost $50. for the gauges and $6. for the freon...

Give it a try, and dont ever be afraid to try it yourself first... you can always pay to have it done if worse comes to worse..

BTW... the instructions that come with the gauges are pretty well explained as well... If you have sufficient freon then your problem lies elsewhere... do a search on how to get error codes from the climate control display on here... that should tell you if you have a bad sensor or component... its the one where you hold the rest and ec button for 5 seconds...

midget fidger

hmm, isnt there something in the ac diagnostics that can tell you the pressure. i think there was...lemme go check

midget fidger

yeah, 7 is Refridgerant pressure sensor. not sure if it works as well or is as specific as an actual guage, but you can try:

The procedures for reading Actual Values go like this: Turn on the ignition, press the "AUTO" button, set the temperature on each side to 72°F (this can be done quickly by pressing both the red and blue arrows at the same time), then press the "REST" button for five seconds or until the left-side display says "1."

The right-side display will then display the in-car temperature. Pressing the "AUTO" on one side makes the positions change up or down (for example, 1, 2, 3, etc). Pressing the opposite "AUTO" button runs the functions in the other direction (for example, 3, 2, 1). The test can be ended at any time by tapping the "REST" button.

CARLSS0N

What if there is a LEAK in your AC system ????????????
can you check it at home
"just buy a UV light and put dye on your system you should be able to do it at home too ???"
no offense too

str8ridin

Good info here.

Correct me if I am wrong, but I've read that our AC systems are sealed (as are most cars) and if you are low on freon, there is a leak in the system. So adding freon or it's equivalent will temporarily fix the system

Also, if your EC button does not turn off, which when there is a problem, it won't, you can turn it off by:

Putting the key into position '2' for 3 seconds, then switch to position '0' for 3 seconds then start the car. Immediatly after starting, push the EC button and it should go off.

Not sure if this does and harm as there is a reason the button will not go off, but if you're in a bind and need the AC, it works.

CERY

Adding refrigerant is not always the answer. There is a reason why the charge was lost. Either some loose fittings, bad bearings, or some seals/gaskets that have dried up and cracked. If I recall correctly, the compressor might have a low pressure switch that will cut out the compressor if the carge is too low. This prevents you from turning on the compressor without a charge.

The fastest and easiest way to tell if you AC system has a leak is to pull your system into a vacuum which requires a vacum pump. You will need to evacuate all the refrigerant first and then pull the system under a vacuum. You leave it overnight and check to see if the system is still under a vacuum. If it is then you are ok to recharge your system. If not you will then have to perform a leak test. This can be done several ways. UV leak detection, nitrogen charge and a spray bottle of soapy water, or a nitrogen chagre with a nitrogen detector.

The process explained above is just a short and skinny. If you want some detailed directions feel free to PM me.

CLK430

ok so if I have the gauge on my cluster at "7" what am i looking for? what kind of read out? the numbers dont mean much to me on the display.


THANKS all for your help...

hangup

this morning i took my C43 for a drive and it was HOT.
i haven't used AC in a while, it's been mostly cold here in Boston area until just a week ago or so.
Sure enough, it blows hot air @#$@!
I did my searching and found this thread. So 7 just displays "LOW" for me
What should that number be i wonder?
anybody knows?
if i find the right number, I'm thinking about adding some freon, driving around for a little while and monitoring the pressure. If there is a significant leak i'll to and AC shop to locate and fix it. But first i'd like to find out if there is a leak.

hangup

i forgot to mention that the numbers, as far as i know, should be pressure in bar.
for example, 200 would be 20.0 bar.
anything above 28 bar is bad, too much. below 2 is too low.
i need to know the exact value though . . . i'll do some research if i find out i'll let you know.
i *think* it might be something like 20 . . . but that's just pure speculation on my part.

hangup

so i found a few things about the pressure. depends on the temp.
it seems like it should be about 10bar at 20C and go up to about 22bar at 40C.
also, in my case the diagnostics show "LO" for 8 and very high temp for 8, that temp is a bit higher than the outside temp, about 20F higher. i think it was the engine compartment temp at the time of the test.
does that indicate that i probably have very little refrigerant left there if any?
I want to isolate one last thing:
it's either (most probably) a leak and i have no freon left or the pressure sensor went bad. i think the temp sensor reading pretty much proves the leak theory, i doubt both sensors would go bad at the same time . . .
what do you guys think? am i way off base here with my analysis? i've not had the pleasure to deal with the A/C yet

sorry for too many messages, i promise this it the last one for today

midget fidger

yeah, the pressure and temperature should be related. PV = nRT where P is pressure, V is volume of the gas (which is constant in this case), n is the number of moles of gas, R is a constant, and T is temperature. P = nRT/V so as T goes up, P should go up too.

CERY

This may help out. http://www.csgnetwork.com/r134apresstempconv.html

hangup

thanks! i studied physics a little bit 10 years ago so i still remember the basics.
I bought a bottle of refrigerant with a gauge on it at advanceautoparts for 20+ bucks today.
I then put the AC in diag and set it to display the high side pressure.
I hooked up the gauge and the bottle to the low side and it was low. Not 0, but close.
The bottle that came with the gauge had 583g or something. I think the full charge is at least 750.
So i put the AC on to full and started to add the gas. At some point the compressor relay "clicked" and i started to get something on the high side. 2bar and climbing.
I basically emptied the whole bottle and AC was blowing the "not so cool" air, but definitely not hot. It was 90F+ on the outside.
The pressure on the high side reached 16bar and then the fan kicked in.
It quickly lowered the pressure to something like 10bar.
I reallized i needed to pay attention to both highside pressure and highside temp.
I got back to the store and bought another bottle with 340g for 10 bucks. I already had the gauge and the connector is the same.
I've started to add more and everytime the fan would hit i'd slow down and wait for it to drop to some stable point and then i'd look at the temp and pressure on the high side and do some calculations and eventually decide if i wanted to add more or not.
More, more, more were my decisions. It goes very, very slowly.
The first bottle must have taken 10+ minutes and let me tell you something . . . you are standing outside, hood opened, enigine running, very hot. I was getting scared that the bottle might explode but since you're puming it in it cools down so you are OK as long as you don't stop for too long. It says on the bottle that you are in trouble if you get to 120F+
Second bottle was at least another 7-8 minutes until the wife (she was shouting the values from the console at me) asked if she could sit in the car and shout from there.
At this point i figured it must have been nice in the car. Yep! it was cool!!!
I decided to be on the cautions side and not fill up anymore. I never hit the 20bar when the "high" fan is supposed to kick in, but i think AC works OK so maybe the "high" fan is for higher outside temps like 110 or something. TX, AZ, etc
So all in all i'm happy for now.
I'm not sure if there are leaks, i guess i was supposed to use the AC every month or so to lubricate the system but i didn't know so i screwed up and haven't used it for almost a year. While i was driving back to the store between the first and the second bottle i was looking at the temp and the pressure on the high side. They went higher when i drove slower. On the freeway the pressure dropped to something like 6bar. In stop and go it was up to 12. So far it doesn't look like it leaks quickly. If there is a leak, it must be slow.
I also noticed that when i shut off the AC the pressuge gauge on the low side jumps up significantly, into the red zone. so if there is a leak my guess is it may leak quicker with AC off.
Basically i'll keep measuring the pressure and temp on the high side and if it leaks i'm going to have to put a die in or something.
Guys at advanceautoparts didn't know what the die was, but tried selling me the "good stuff with the sealant". I decided against that. If i screw it up with the sealant it will for sure be big bucks. If it just keeps leaking at least i'm not going from bad to worse here.
I wish everybody luck with their ACs. Overall the process is pretty simple. You may need someone to help you to shout out the readings and you need at least 30 minutes not to rush things. I was glad the connector is common and cans in these retail stores have the same connector.
Just filling it up is definitely a DIY, but leaks are probably not unless you are very good with these things. I'm probably not going to fix the leaks myself, but i would put a die and look around trying to locate them because i don't want someone to BS me.
It usually goes like this . . . Oh, so you have an AMG . . . hmm. at least a grand to start with!

hangup

lost a lot overnight, pressure down to under 1bar on the highside
must be a large leak . . .
i'll put the UV dye in tonight and go from there.

CERY

A helpful procedure in filling up would be to imerse the refrigerant bottle in a bucket of hot water. That will help the refrigerant boil into a vapor and get absorbed into the system faster. If you noticed, the bottle must have been getting pretty cool (might even frost up if the humidity is high). Keeping the bottle warm and in the upright position is the best way.

MAKE SURE YOU DON'T HOLD THE BOTTLE UPSIDE DOWN! YOU WILL FEED LIQUID REFRIGERANT INTO THE COMPRESSOR. Compressed liquids = BOOM!

hangup

well, having to keep the bottle on top of the engine cover warms it up quite a bit too
i've added a dye today. i used dupont premixed SUVA product.
so far it is still blowing cold and holding the pressure but it will probably all change soon.
dye is hard to see with a little pen led-driven flashlight i got from advanca autoparts, gogles help but it is still tough unless you work at night.
so i went outside to check on in once it got really dark.
i *think* i see tiny drops on the compressor but they are not grouped in any particular spot. i tried looking from underneath too, but not much luck so far.
i can clearly see it on the low side port itself so i think i know what it should look like.
i'll just keep checking on it every night for a few days . . .
the worst thing is if i think it's the compressor and replace it and then find out that the evaporator leaks too . . .
at this point it's tough to tell if evaporator is part of the problem or not.
i wish i could get under the dash without removing too much stuff, just some plastic panels on the bottom hopefully and point the UV light in there . . . anybody has a good description on how to do that? is it even possible?

midget fidger

when my guy put dye in my system, he used a yellow glasses to show it...i think he also used a black light, but im not sure if i'm just imagining that part haha

RED-CLK

Hangup, If you see drops around front of compressor, it could be a leaking seal, the whole compressor would not need to be replaced, just the ceramic seal that can be replaced for a lot less money and it doesn't have to be done at the dealer.

hangup

yeah! i have the yellow glasses, without them all you see is the light itself
basically when you buy a penlight it comes with the glasses. 15bucks in advanceautoparts. battery included.
light looks like it really sucks, not very powerful, but the glasses are OK.
basically don't try to use the light when it's not completely dark outside - useless, not enough power.
but in the complete darkness it works OK.

this morning i was still using the AC and it's still OK. SOB! as soon as i put a dye in it's not leaking anymore ))
i think what must have happened is that because i didn't know that compressor needed to be used and i kept using economy mode in winter i ended up not lubricating it for a long time and now that i lubricated it a bit while charging it with some oil/r134a combo (the first can i used) maybe it's getting better. first night after the first charge it really leaked quick. but now the second night after the second charge it seems to be OK. weird. i'm going to have to wait longer i guess.

hangup

good to know! i think there are some in the front underneath, but i'm not sure. there were some tiny drops on he back of it too, it kind of looked like mist if you know what i mean. but it wasn't coming out of any seal or anything . . . so i'm not even sure it's the dye. the light is not very powerful and some things reflect and look like they glow . . .
perhaps i need a better light and i think i need to run if for longer. if it keeps leaking i should see more dye there i'd think.
btw, is the dye stable enough to last for a few days? i know that dupont marketing materials on their website say it is, but i'm asking it as a practical question

hangup

actually i found out that i was thrown off course by those tiny mist looking drops.
they were really only seen with the glasses and were kind of all over the place not coming out of any seal or what not. then i noticed some on the ESP module too.
i started to doubt that maybe it's oil or something else that just looks this way in the UV light with those glasses on. pulled out the dipstick, no, definitely not the oil
but wait . . . then i noticed a few of these misty drops on the other side, on the alternator! what the heck!? maybe it's rust or something. but i didn't see any rust there.
i went under the car again. a few misty drops on the front of the compressor, but then i see it on some other parts too.
here i notice the ground wire that was supposed to be connected to something but it's CUT! wth? well, maybe i'll come back when there is some light, remember this is all in complete darkness.
then i finally decided to look at the radiator and here it was! i can even see it easily without glasses. it's HUGE, but it's hiding behind the driver side fan (close to the high side port).
it's definitely a large leak. that's how the tiny misty-looking drops were getting everywhere . . . fan was blowing that stuff out of the radiator into the car.

so now i need to figure out how the radiator is built on these cars. is it all one piece or is the AC piece separate . . . anyways, back to the books

Thanks everybody for suggestions and info i think i was able to figure out what the problem is in just a few hours even though i'm not a mechanic at all in large part due to help i got from this forum!