HTBenz

Ok I filled my a/c with 134 and oil and it ran fine. Problem is that after a few days it lost pressure and the A/C stopped blowing. So I go and buy some lube that seals small leaks caused by gaskets and put it in the system. It builds pressure so I let some of it out after running the system for a few hours. Thing is now after refilling the system to the correct pressure the EC button comes on automatically and I can not get it to turn off. What could be causing this? I reset the system by unplugging the battery and still the EC button comes on when starting the AC and will not turn off. Has anyone else had this issue.....it fills like 100+ here in Houston so I have to get this fixed like soon.

Thanks.

E-Klasse

The EC light comes on because of a low pressure indication in the AC system. Do a search on here for the diagnostic mode for the AC controler. It will tell you what pressure it is reading. The sensor could be bad.

sosh

The leak stuff you used is really not good for the system. Leaks should be found and corrected properly. This stuff could have ruined the sensor and perhaps clogged the drier. Getting this stuff out is a major job and a big expense. Good luck

hangup

do a search and you'll find my story, i'm going thru the same thing now.
don't put any sealants in unless you are giving up on you A/C system. very expensive to replace everything!
if you clog your evaporator or compressor especially . . .
do buy a dye and UV light and gogles. find a leak. fix it, recharge it.
i found my leak was in the condensor.
i've removed the faulty condensor and now looking for the correct part to put back in there.

sosh

He already ruined his system with the leak stopper. Its too late. Now is going to cost him maybe a complete new system if he wants A/C.

HTBenz

Dear god please don't say such things!!!! I am going to sell this car for 4K so fast if this is true.

sosh

Be pretty hard to sell with the A/C inop. If you think the car is worth only 4K you may spend that much getting the A/C fixed.

HTBenz

The car is worth way more that 4K but I will have no issue selling it without AC for that price. I sold my older 89 model with the main wire harness burnt for $1500. The guy that got it had no way to even start it and I had a line of people that wanted it for that price with over 150K.

lexrex

There are several people on these forums who have used an A/C leak sealer additive with good results for fixing evaporator leaks. Just search the archives. I personally wouldn't use the stuff, but I wouldn't go jumping to conclusions, sosh.

HTBenz

Ok I had to search my butt off but I found out how to run the test and this is what I got:

B1232 Refrigerant Sensor
B1241 Refrigerant Fill
B1234 Sun Sensor
B1235 Emission Sensor

Now I did let the coolant back out of the system so I know why I have the second code but can anyone shed some light on what they mean by the other items? Please!!!!!

hangup

i'm not quite sure what is going on.
you left the refrigerant out? why? or has it leaked out?
keep in mind you don't want the moisture in there, especially now that you've added the sealant. sealant reacts with the moisture and turns into solid.

1) hookup to the low side, take a look at the pressure. if zero, stop here. you have a leak.
2) if normal, turn the a/c on (cold, high fan), go to diag more (press REST for 6 secs) and read the high side pressure (7) and temp (8). If high side pressure is not "lo" (or something small, depends on temp) stop here. you don't have a leak.
if it's "lo" while pressure on the low side is not that means that you have a leak and that compressor is not compressing
that may just be because the high pressure sensor reads "lo" and compressor is trying to protect itself and not kicking in. in that case you can add more into the low side. it may get into "yellow" for a little bit but don't worry. make sure you don't charge with the bottle upside down (or at least not for too long, or liquid gets into the compressor and you are done) and once you get into the yellow don't rush it, give it a few minutes.
eventually pressure on the high side will rise and the compressor should kick in. when that happens pressure on the low side will start dropping dramatically and you need to start charging it "for real". keep the bottle on something warm but not too hot, like the engine cover. if the bottle gets too cold the "stuff" is going to start coming out even slower. from that point on do not go into the yellow on the low side and keep monitoring the high side. depending on your temp you may hit 16 or 17 then fan will kick in and the temp will drop and so will the pressure. if you ever get to 20 it will really kick in hard. do not exceed that. have someone else listen to the a/c by slowing down the fan every once in a while and listening for the hissing sound to go away. once it's not hissing anymore you are at about full charge. don't try to overcharge it btw, this charge is just to find the leak. so putting in a couple of 300 gram cans is enough (assuming you are starting with 0).
3) your objective is really to find if you have a leak or not and if you do, you need to find out where it is. this is done with a dye. i've used dupont product and it worked quite well.
4) as a side effect of charging it with r134a w/dye you'll know if the A/C is working properly or not. that will test your compressor, sensors and the rest of the system.

i'm not very sure about the codes. some may mask others. i'd read all sensors using the a/c diag mode to see if the values make sense. if the circuit for a particular sensor is open or short it will display some weird value, so you'll know it's suspicious.

some idea on what i used (got that stuff from local advanceautoparts)
dupont r134 w/dye: $11.88
UV light w/gogles: $15 or something like that. light is not very poweful so for best results use at night.
inspect all hoses, compressor, receiver/dryer and the condensor. if you still can't find a leak then prepare for the worst . . . it may be evaporator.

this is all easy stuff as long as you have done the research, mentally wrote down the plan of attack and follow logical step by step troubleshooting.
people will tell you that the sealant has destroyed your system, etc. but don't give up. the fact is, nobody knows what has happened before you find out and tell us. i hope you do, your experience may benefit others. the season for A/C fixing has started . . . when i went to the store to pick up the refrigerant w/dye just about everybody in the store was picking up the same stuff

sosh

This guy does not have a clue as to what he is doing. He has already damaged the system by using that snake oil leak stop and by letting all the gas out causing moisture to enter. The more he is told the worse he gets!! Let him alone and let him suffer in a real hot car. Maybe then he will wake up and take it to a dealer or A/C shop and have the problems corrected. He does have a leak, he has damaged the system and he needs to learn.

HTBenz

Thanks HANGUP for trying to help at least you were not a smart a$$ that claims to know it all but has not offered anything of real worth to this thread. Anyway I was due to go into the shop today but forgot to secure my appointment so I will have to go Thursday. I will give an update and I am not stupid enough to go to the dealer with an almost 10 year old car. A good Benz shop will due for a fraction of a dealer.

I still have my CTS so I think after I fix the A/C I am going to trash this problematic automobile.

lexrex

HTBenz,

Your problem may simply be a bad sensor. The "B1232 Refrigerant Sensor" code indicates that your refrigerant pressure sensor may be faulty. Remember that the EC light will come on to shut off the compressor to protect it from low pressure damage. When your pressure sensor goes bad, it can shut off your compressor even though you have a full charge.

Have you looked at the actual values for the various sensors? (If you haven't, start the ar and hold down the REST button for about 5 seconds until the display changes. Press the left AUTO button to cycle.) What are the values for #7 & #8?

As you noted, the refrigerant fill code is there b/c you let the R134 out of the system.

All the sun sensor does is turn up the blower speed a little bit when strong sunlight hits your dash. (It's the sensor in the center of your dash near the windshield.) It's unrelated to your current A/C problem.

The emission sensor monitors the air quality and automatically switches to recirculate mode if it detects smog in the outside air and your charcoal filter is turned on. Again, unrelated to your current A/C problem.

I really doubt that your leak stopper additive will clog your A/C components as others have suggested. But if it does, it would probably only mess up your receiver-drier. The receiver-drier is a relatively inexpensive part.

Hope this helps.

HTBenz

Thanks LEX that makes perfect sense to me. I think I will price the sensor and I will start over.

fast_car

Have you ever fix the A?C problem on your car, my wife 1999 E320 AC only blow cool for a few minutes and after that just air.

Any one car share or point where to check for

Thanks

HTBenz

Yep just got it done and Lex was right the sensor(pressure sensor) was clogged from additive that I put in the system. No the whole system was not damned to hell. I did have a small leak I don't know what he did to fix it but he did.

hangup

cool, congrats!
i didn't know the sealants could damange the sensors, i thought it was only creating issues when there is moisture in the system.
could you share some details on how much was the repair? was it a big job, small job, how much were the parts, etc.
just in case someone else has to fix the same thing.
now we know how to diagnose this particular problem (reading the sensors) so that's good for everyone!

vinamg

This is a common problem. Check and replace the evap temp sensor ($40).

JimE430

These posts sound a little scary. The AC system is a very complex system that is designed to be serviced my experienced techs, with the correct equipment. You must use correct amounts of oil and gas, then have the tools to measure the correct pressures. A leakdown test must be performed, as well as a complete inspection of the entire AC system. This is not a 69 Chev. (even then you had to have a bit of expertise) I know some will dissagree, but I would NEVER put an additive in my AC system (just looking for trouble) Consult someone you trust, replace what parts you can, BUT let the mechanic do the recharge and leak test.
Is it possible the EC (Economy, AC off) is being tripped because you have too much pressure?
Good luck, Jim

HTBenz

The total repair cost was $142 for the labor, refrigerant, and the sensor thing. My repair guy gives me really good prices at times. I suspect it would cost much more from another shop. Also A/C systems are very similar and just because it is a Benz does not make it special. Someone that is familiar with A/C system in general can work on it without issue. Also pressure gauges come with most reg. and they have guides on them to tell you where the safety zones are.