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Hi, I have a 2009 mercedes benz c300. Last week the battery was dead, so I tried to jump the car, it gave a little to no life, so I went out and bought a new battery. When i set up everything and turned the car on I noticed that the air conditioning wasnt flowing, it has power when it is turned on though, and the A/c tube that runs through the car gets cold, but it isnt blowing out any air. whats the problem?
Hi, I have a 2009 mercedes benz c300. Last week the battery was dead, so I tried to jump the car, it gave a little to no life, so I went out and bought a new battery. When i set up everything and turned the car on I noticed that the air conditioning wasnt flowing, it has power when it is turned on though, and the A/c tube that runs through the car gets cold, but it isnt blowing out any air. whats the problem?
97 E Class 420 AC issues New to forum- Any help would be appreciated
Hey guys hope all are well was hoping to get some insight on my ac issues with my 97 E 420 with 45000 original miles on it- I have been reading the stickies about AC issues so I decided to run the diagnostics and then post and see what you guys thought prior to going to the Indy-
Heres what I found on the codes
Got a 1227- outside temp indicator
1235- Series Interface K1 connection to Instrument cluster-
cleared these codes they never came back
I ran the other diagnostics and got this: all converted to fahreinheit
1- 84.2
2-80.6
3-87.8
4-87.8
5- 86
6-143.6
7-00
8-80.6
outside temperature is 84-- My compressor is not engaging and my EC light is not in the stuck "ON" position - Any help or thoughts would be greatly appreciate- Thanks Cole ( PS I reposted as I realized I had posted in the wrong spot
B1416 – Coolant circulation pump (M13)
B1419 – Electromagnetic clutch (A9k1)
B1459 – Series interface (K2) connection to instrument cluster (
B1234 – Sun sensor (B32)
Here are the results from my on board Monitoring or Diagnostic System. There were a couple of more I forgot I think it was one of the sensor codes. Possibly [B1230 – Evaporator temperature sensor (B10/6)]
I cleared them and I am going on a long drive today to my drilling rig so I will check them again when I get there to be sure. Pretty sure the clutch code is because I had a poor connection and it wasnt receving or showing the correct voltage which I fixed for now. I changed my expansion valve and there has been no improvements. My carsoft diagnostic software continues to throw code P20ce / Cooling system pressure to high ( Airco). I tried putting a couple cans of freon in today with my manifold gauges and I finally saw the Clutch come on for a few moments. Once the clutch shutoff it didn't start working again.. there is a possible blown fuse I am going to check for next. I wanted to see if I could get it to do anything at all before I go rent a vacuum pump and pull a vacuum on it. It builds up so much pressure so quickly that I can barely even get the freon to go in it. I dont believe I have any leaks, but I am not 100% positive on that yet. I want to check on my duovalve next and make sure it isn't stuck shut creating the pressure build up just in case. I guess it is also possible from what I have been reading on here that my evap temperature sensor could be faulty. Any advice you all could share with me would be awesome!
For full troubleshooting you will need to read the sensors at least 1 more time in the morning before engine start and before sun will warm up the cabin.
But from what you already have - you can ignore coolant pump and sun sensor for AC (fix the pump for heating season).
Check your connections at instrument cluster, clutch and evaporator.
Your system at 1 bar is almost empty. Once you get the above check and errors cleared - put a can of r134 with dye in it and nothing else.
Hi all, I have a 2000 E320 that seems to have a chronic A/C problem that just won't go away. The A/C starts cold then the EC light goes on after 10 minutes of driving. I payed a local mechanic $1200 to replace the condensor, replace a couple of belts, replace the blower motor, replace the A/C pressure switch, replace the blower motor resistor, replace the drier to expansion valve hose, and vacuum and recharge the system several times.
Before I brought it to the mechanic I got some error codes like B1241 and B1234. After the mechanic worked on it the EC light goes on still but when I look at the error codes there is only "E FF". I can clear the code and turn the EC light off. Another thing to note is when I'm parked for 40+ minutes the A/C blows cold on the passenger side and switches between warm and less warm on the driver side. The #7 pressure reading never goes above 07 and drops down to 03 when I'm driving. The mechanic says the pressure is good when tested with the charging station.
Any advice you can give would be great. The sad thing is I was willing to pay the mechanic more money (to an extent) to fix the A/C but he has given up on it.
Opening the system like that, yes they should have replaced the dryer.
What should I do now? I imagine this is something I need to bring to the shop for. I'm not DIYing this any further than putting some refrigerant in so I guess I need to bring it to another shop and tell them that's what I read on a forum.
I think you should start with the basics. Run some dye in the system and check for leaks. Or have a shop perform this with a sniffer. If there is a leak pray its in NOT in front of the firewall.
I read depending on outside ambient temp #7, you should have between 7-20 bar pressure 17-20 on higher end when idle or stopped and it drops on the move down to 7-10ish as air goes through the condenser #3 & #4 should be 35-40 and that number can fluctuate too.
I recently replaced my entire system, including the dreaded Evap, so there are my number range from a brand new system.
Find a competent Independent MB shop.
Last edited by Tall Giraffe; Jun 29, 2019 at 10:52 AM.
I think you should start with the basics. Run some dye in the system and check for leaks. Or have a shop perform this with a sniffer. If there is a leak pray its in front of the firewall.
I read depending on outside ambient temp #7, you should have between 7-20 bar pressure 17-20 on higher end when idle or stopped and it drops on the move down to 7-10ish as air goes through the condenser #3 & #4 should be 35-40 and that number can fluctuate too.
I recently replaced my entire system, including the dreaded Evap, so there are my number range from a brand new system.
Find a competent Independent MB shop.
There is a hissing sound that seems to get louder as the air gets cooler.
The mechanic ran the sniffer over the ac system and found leaks in the condenser and the dryer to expansion valve hose which he since replaced.
The mechanic said the evaporator is fine but who knows if he knew for sure.
Thanks for your help.
How much did it cost to replace the entire a/c? How much of that was the evaporator? I can’t imagine spending more money than what my car is worth.
Hopefully the mechanic placed the exact weight of refrigerant in the system but to get hiss means its leaking out or its under filled. How long after you had it refilled did it start hissing? Also the system really needs to hold a vacuum -27 or better for an hour solid.
I discovered my evaporator leak ( I always knew it was bad) by observing dye coming out the AC drain line. Mine came out of my driver side drain underneath the car. A sniffer might be able to detect it through the center vents but lets hope for the best. If it is your evaporator then you will need to make a choice cause the labor to replace that will be massive.
All in all I spent about $600 in parts and that's everything- condenser, 2 driers, compressor, expansion valve, O rings, PAG oil, pressure switch, evaporator, flush kit for the line.. I stole many of the parts by getting great deals online using coupon codes and rewards points. For example, I bought my compressor, the latest revision OEM, for $201 brand new and the evap was $156 using points.
My labor I'd say 4 ish hard days in total. If I wasn't able to do all my own labor, the choice to keep the AMG would of been heart breaking tough one.
Oh 2 driers because I opened the system twice. It only needs one.
Last edited by Tall Giraffe; Jun 28, 2019 at 10:21 PM.
Hopefully the mechanic placed the exact weight of refrigerant in the system but to get hiss means its leaking out or its under filled. How long after you had it refilled did it start hissing? Also the system really needs to hold a vacuum -27 or better for an hour solid.
I discovered my evaporator leak ( I always knew it was bad) by observing dye coming out the AC drain line. Mine came out of my driver side drain underneath the car. A sniffer might be able to detect it through the center vents but lets hope for the best. If it is your evaporator then you will need to make a choice cause the labor to replace that will be massive.
All in all I spent about $600 in parts and that's everything- condenser, 2 driers, compressor, expansion valve, O rings, PAG oil, pressure switch, evaporator, flush kit for the line.. I stole many of the parts by getting great deals online using coupon codes and rewards points. For example, I bought my compressor, the latest revision OEM, for $201 brand new and the evap was $156 using points.
My labor I'd say 4 ish hard days in total. If I wasn't able to do all my own labor, the choice to keep the AMG would of been heart breaking tough one.
Oh 2 driers because I opened the system twice. It only needs one.
That’s impressive.
It started hissing right away.
My mechanic said he followed the guidelines on the exact amount of refrigerant to add. I think maybe he half-assed the vacuuming after the third time doing it.
I understand it’s an old car and the ac won’t kick out as much as it used to but I would like it to not shut off into safety mode after 10 minutes of driving it.
With my defective evaporator, my system would not hold below -23
If it doesn't hold better than -27, you still have an issue and youll continually lose refrigerant. I still think you need to replace that drier, but you need to find out why the system is under charged first. Being an old car doesnt mean the car wont hold charge, thats simply a mechanical issue.
Here is my thread. It may contain more info to help you and went through the process I took.
Last edited by Tall Giraffe; Jun 29, 2019 at 11:21 AM.
With my defective evaporator, my system would not hold below -23
If it doesn't hold better than -27, you still have an issue and youll continually lose refrigerant. I still think you need to replace that drier, but you need to find out why the system is under charged first. Being an old car doesnt mean the car wont hold charge, thats simply a mechanical issue.
Here is my thread. It may contain more info to help you and went through the process I took.
So something incredible happened today. I got in the car when it was 86 F out turned on the engine and monitored the climate control readings for a few minutes. The pressure was a little higher (#7 went up to 08). I was confident enough to take the car for a little drive around the block and monitored the readings while driving. #7 went up to 12 after a minute of driving and then up to 15! The A/C came out cold on both the driver and passenger side with no hissing. On my 5 minute drive #7 fluctuated between 10 and 15. I'm not sure what to make of this. The only difference between yesterday and today is that it was sunny yesterday and the temp was a few degrees higher. Is it possible the A/C just needed a few days to circulate? I picked it up from the mechanic on Monday. The true test will be when I take it out for a 30+ minute drive on an 86 F day. Here are my readouts from today's drive...
I would start with calibration test.
You can try to make assumptions from performance test, but not knowing if sensors are accurate, that all might be worthless.
So something incredible happened today. I got in the car when it was 86 F out turned on the engine and monitored the climate control readings for a few minutes. The pressure was a little higher (#7 went up to 08). I was confident enough to take the car for a little drive around the block and monitored the readings while driving. #7 went up to 12 after a minute of driving and then up to 15! The A/C came out cold on both the driver and passenger side with no hissing. On my 5 minute drive #7 fluctuated between 10 and 15. I'm not sure what to make of this. The only difference between yesterday and today is that it was sunny yesterday and the temp was a few degrees higher. Is it possible the A/C just needed a few days to circulate? I picked it up from the mechanic on Monday. The true test will be when I take it out for a 30+ minute drive on an 86 F day. Here are my readouts from today's drive...
Just an update: I took my car out for two 50 minute trips on Sunday when it was mid 80's F out. The A/C stayed on the whole time and came out all vents cold. The #7 pressure hovered around 12 on city streets and 06 highway driving. I'm hoping it's stays above 06 on long distance highway driving. It's 89 F today and it's still coming on nice and cold after a few minutes of starting my engine. Next test is a long distance highway drive but for now I'm feeling pretty good about it.
Just an update: I took my car out for two 50 minute trips on Sunday when it was mid 80's F out. The A/C stayed on the whole time and came out all vents cold. The #7 pressure hovered around 12 on city streets and 06 highway driving. I'm hoping it's stays above 06 on long distance highway driving. It's 89 F today and it's still coming on nice and cold after a few minutes of starting my engine. Next test is a long distance highway drive but for now I'm feeling pretty good about it.
Output still seems a little low. I feel like those numbers at that temp a hiss should be there. Was there?
89 degrees, 74% humidity here today and when I checked today Im 17 - 09 bar.
Just an update: I took my car out for two 50 minute trips on Sunday when it was mid 80's F out. The A/C stayed on the whole time and came out all vents cold. The #7 pressure hovered around 12 on city streets and 06 highway driving. I'm hoping it's stays above 06 on long distance highway driving. It's 89 F today and it's still coming on nice and cold after a few minutes of starting my engine. Next test is a long distance highway drive but for now I'm feeling pretty good about it.
You are like my wife. I tell her "turn left" and she promptly turns right.
All those numbers are worthless as variable output compressor can operate different pressures that depend on other 8 sensors.
When we don't know calibration, it is like OJ Simpson trial. "garbage in = garbage out"
Output still seems a little low. I feel like those numbers at that temp a hiss should be there. Was there?
89 degrees, 74% humidity here today and when I checked today Im 17 - 09 bar.
The hiss comes and goes. It does seem to hiss when #7 is low. I have the same weather here in NY and when I checked yesterday it was at 14 bar. I agree it should be higher. I don't like to see it drop down to 06 on the highway but as long as the a/c stays on I'm not too concerned.
Well I would say that sure your AC will operate given the below average numbers but for how long? I think Kajtek1 and Plutoe has valid points/plausibilities. I believe running your system this way may ultimately cause more damage in totality.
Below is a chart I used as a close reference during my repair to understand numbers as suggested by MB. My system numbers, slightly different, matched another member with same car who also replaced his entire system as well.
You are like my wife. I tell her "turn left" and she promptly turns right.
All those numbers are worthless as variable output compressor can operate different pressures that depend on other 8 sensors.
When we don't know calibration, it is like OJ Simpson trial. "garbage in = garbage out"
How about some more info on calibration then? How do I get it calibrated? How much does it cost? Is this a DIY job?
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