Need Air Conditioning Help
Thread Starter
Newbie
Joined: Oct 2021
Posts: 14
Likes: 1
From: New England
2006 Mercedes e500 4MATIC, 2002 E320 4MATIC Wagon
Need Air Conditioning Help
The AC on my 2006 Mercedes E500 4MATIC never worked under my ownership until about a few months ago. I was able to get it running after replacing a sensor and recharging the refrigerant. I never used it though until just a few weeks ago when it started getting warmer outside. It worked great for the first couple weeks until I noticed the rear AC vents were blowing very hot air. The front still blew cold. The next day I noticed the front ac started blowing a bit warmer, but I could tell it was still working. The very next day my AC was completely dead and wasn't blowing cool at all anymore. On that day, I replaced the heater control valve at the firewall to hopefully solve the rear blowing hot air issue. It doesn't blow super hot air back there anymore, but my AC doesn't work at all so its not cold. My refrigerant level is still exactly the same as it was the day I filled it a few months ago. No leaks. I'm not sure what would cause my AC to stop working like that. Could it be related to the heater valve issue? I used my scanner to check for codes and I had an error code for the temp sensor in the dome light. I replaced that and I now have a correct temp reading, but my AC still doesn't work. The only fault code I have in all of my cars modules is for a sensor in the driver seat, which I'm sure will not affect my air conditioning lol. The scanner I am using is the iCarsoft CR Max. It's a cheap one but its more than enough for what I need. Any help would be appreciated, thank you!
MBWorld Fanatic!
Joined: May 2021
Posts: 2,527
Likes: 2,044
From: US
2008 E350, 2012 ML350, 2014 E350, 2015 ML350
If the refrigerant is complete, you can set it to LO on both sides and it should work.
When on LO only pressure sensor (check for refrigerant) and the evaporator temperature sensor should control the compressor (prevent freezing in the evap)
does the icarsoft scanner shows pressure and evaporator temperature live?
When on LO only pressure sensor (check for refrigerant) and the evaporator temperature sensor should control the compressor (prevent freezing in the evap)
does the icarsoft scanner shows pressure and evaporator temperature live?
Thread Starter
Newbie
Joined: Oct 2021
Posts: 14
Likes: 1
From: New England
2006 Mercedes e500 4MATIC, 2002 E320 4MATIC Wagon
If the refrigerant is complete, you can set it to LO on both sides and it should work.
When on LO only pressure sensor (check for refrigerant) and the evaporator temperature sensor should control the compressor (prevent freezing in the evap)
does the icarsoft scanner shows pressure and evaporator temperature live?
When on LO only pressure sensor (check for refrigerant) and the evaporator temperature sensor should control the compressor (prevent freezing in the evap)
does the icarsoft scanner shows pressure and evaporator temperature live?
MBWorld Fanatic!
Joined: May 2021
Posts: 2,527
Likes: 2,044
From: US
2008 E350, 2012 ML350, 2014 E350, 2015 ML350
I would not have opened the AC cooling circuit/system w/o first diagnosing it. Opening the system is bound to create more problems, $$, than fix anything if you are not 100% certain about what you are aiming at.
Since you have evacuated and recharged the system more than once already, I assume you :
1 - have access to AC pressure gauges, correct?
2 - know the exact amount of refrigerant required for your car (read label under the hood)
3 - you weighted, or measured the amount of refrigerant, correct?
With the pressure gauges, and the scanner connected you should be able to pin-point the problem, but it requires several measurements and a bit of patience to avoid premature conclusions.
NOTE: since you have opened the circuit already multiple times, be prepared to replace the drier soon (only do so at the hopefully last time you opened again).
Since you have evacuated and recharged the system more than once already, I assume you :
1 - have access to AC pressure gauges, correct?
2 - know the exact amount of refrigerant required for your car (read label under the hood)
3 - you weighted, or measured the amount of refrigerant, correct?
With the pressure gauges, and the scanner connected you should be able to pin-point the problem, but it requires several measurements and a bit of patience to avoid premature conclusions.
NOTE: since you have opened the circuit already multiple times, be prepared to replace the drier soon (only do so at the hopefully last time you opened again).
Thread Starter
Newbie
Joined: Oct 2021
Posts: 14
Likes: 1
From: New England
2006 Mercedes e500 4MATIC, 2002 E320 4MATIC Wagon
I would not have opened the AC cooling circuit/system w/o first diagnosing it. Opening the system is bound to create more problems, $$, than fix anything if you are not 100% certain about what you are aiming at.
Since you have evacuated and recharged the system more than once already, I assume you :
1 - have access to AC pressure gauges, correct?
2 - know the exact amount of refrigerant required for your car (read label under the hood)
3 - you weighted, or measured the amount of refrigerant, correct?
With the pressure gauges, and the scanner connected you should be able to pin-point the problem, but it requires several measurements and a bit of patience to avoid premature conclusions.
NOTE: since you have opened the circuit already multiple times, be prepared to replace the drier soon (only do so at the hopefully last time you opened again).
Since you have evacuated and recharged the system more than once already, I assume you :
1 - have access to AC pressure gauges, correct?
2 - know the exact amount of refrigerant required for your car (read label under the hood)
3 - you weighted, or measured the amount of refrigerant, correct?
With the pressure gauges, and the scanner connected you should be able to pin-point the problem, but it requires several measurements and a bit of patience to avoid premature conclusions.
NOTE: since you have opened the circuit already multiple times, be prepared to replace the drier soon (only do so at the hopefully last time you opened again).
I really appreciate your response, any bit of info really helps. Thank you!!
MBWorld Fanatic!
Joined: May 2021
Posts: 2,527
Likes: 2,044
From: US
2008 E350, 2012 ML350, 2014 E350, 2015 ML350
Forum members are willing to help you, but you need to post not only qualitative data, but quantitative data,
What you consider normal, means nothing since that is a relative term, and data must not be biased.
Could you please do the following:
0 - Report ambient temperature (to verify if data from AC gauges makes any sense)
1 - Connect the AC pressure gauges with the car OFF, better if it is cold
2 - Connect the scanner, and from the AC live data monitor values for
4 - Report the values in the scanner
5 - Start the car, ON, no AC yet wait until it reaches normal temperature if not already there
6 - Turn AC ON, Maximum Fan Speed , @1500 RPM, and LO setting on both vents, and if the rear are adjustable those as well.
7 - Report data from AC gauges (LO and HI), and scanner
Hopefully, we can make sense of the data and suggest the next step
NOTE: you forgot to answer the question regarding the amount of refrigerant to used to refill/recharge, and how you did it.
What you consider normal, means nothing since that is a relative term, and data must not be biased.
Could you please do the following:
0 - Report ambient temperature (to verify if data from AC gauges makes any sense)
1 - Connect the AC pressure gauges with the car OFF, better if it is cold
2 - Connect the scanner, and from the AC live data monitor values for
Refrigerant Pressure
Refrigerant Temperature (I think 2006 has both sensors)
Commanding value for the compressor, Torque, Amperage, whatever the scanner calls it.
3 - Report pressure on the gauges, Low and High. Hopefully the sameRefrigerant Temperature (I think 2006 has both sensors)
Commanding value for the compressor, Torque, Amperage, whatever the scanner calls it.
4 - Report the values in the scanner
5 - Start the car, ON, no AC yet wait until it reaches normal temperature if not already there
6 - Turn AC ON, Maximum Fan Speed , @1500 RPM, and LO setting on both vents, and if the rear are adjustable those as well.
7 - Report data from AC gauges (LO and HI), and scanner
if you are able to touch the suction hose near the compressor (the thicker one), it should be a lot colder than ambient temperature, is it ?
anything abnormal on the gauges, like fluctuating pressures
8 - Turn the car OFF, and notice the AC pressure gaugesanything abnormal on the gauges, like fluctuating pressures
HI must lower toward original pressure
LO must go higher toward original pressure
Measure how long it takes to go towards original pressures, is it 5 min, or 30+ min?
You can make a table, and post the table. Let me show one https://mbworld.org/forums/e-class-w...ml#post8600850LO must go higher toward original pressure
Measure how long it takes to go towards original pressures, is it 5 min, or 30+ min?
Hopefully, we can make sense of the data and suggest the next step
NOTE: you forgot to answer the question regarding the amount of refrigerant to used to refill/recharge, and how you did it.
Last edited by JCM_MB; May 19, 2023 at 03:25 PM.
Thread Starter
Newbie
Joined: Oct 2021
Posts: 14
Likes: 1
From: New England
2006 Mercedes e500 4MATIC, 2002 E320 4MATIC Wagon
Forum members are willing to help you, but you need to post not only qualitative data, but quantitative data,
What you consider normal, means nothing since that is a relative term, and data must not be biased.
Could you please do the following:
0 - Report ambient temperature (to verify if data from AC gauges makes any sense)
1 - Connect the AC pressure gauges with the car OFF, better if it is cold
2 - Connect the scanner, and from the AC live data monitor values for
4 - Report the values in the scanner
5 - Start the car, ON, no AC yet wait until it reaches normal temperature if not already there
6 - Turn AC ON, Maximum Fan Speed , @1500 RPM, and LO setting on both vents, and if the rear are adjustable those as well.
7 - Report data from AC gauges (LO and HI), and scanner
Hopefully, we can make sense of the data and suggest the next step
NOTE: you forgot to answer the question regarding the amount of refrigerant to used to refill/recharge, and how you did it.
What you consider normal, means nothing since that is a relative term, and data must not be biased.
Could you please do the following:
0 - Report ambient temperature (to verify if data from AC gauges makes any sense)
1 - Connect the AC pressure gauges with the car OFF, better if it is cold
2 - Connect the scanner, and from the AC live data monitor values for
Refrigerant Pressure
Refrigerant Temperature (I think 2006 has both sensors)
Commanding value for the compressor, Torque, Amperage, whatever the scanner calls it.
3 - Report pressure on the gauges, Low and High. Hopefully the sameRefrigerant Temperature (I think 2006 has both sensors)
Commanding value for the compressor, Torque, Amperage, whatever the scanner calls it.
4 - Report the values in the scanner
5 - Start the car, ON, no AC yet wait until it reaches normal temperature if not already there
6 - Turn AC ON, Maximum Fan Speed , @1500 RPM, and LO setting on both vents, and if the rear are adjustable those as well.
7 - Report data from AC gauges (LO and HI), and scanner
if you are able to touch the suction hose near the compressor (the thicker one), it should be a lot colder than ambient temperature, is it ?
anything abnormal on the gauges, like fluctuating pressures
8 - Turn the car OFF, and notice the AC pressure gaugesanything abnormal on the gauges, like fluctuating pressures
HI must lower toward original pressure
LO must go higher toward original pressure
Measure how long it takes to go towards original pressures, is it 5 min, or 30+ min?
You can make a table, and post the table. Let me show one https://mbworld.org/forums/e-class-w...ml#post8600850LO must go higher toward original pressure
Measure how long it takes to go towards original pressures, is it 5 min, or 30+ min?
Hopefully, we can make sense of the data and suggest the next step
NOTE: you forgot to answer the question regarding the amount of refrigerant to used to refill/recharge, and how you did it.
