i have a c240 4matic the a/c was working and then it just stopped i keep it on auto. now the little red light is on, on the ac/off button and will not go out the pressures are balanced and good please any helped would be good i am thinking about getting a a new cluster but firgured i would ask first thanks

 

When the compressor isn't on the pressure should be the same on both high and low side, that's normal. What are the pressure readings?

Alan.

 

they are equal but i can't remimber the the number in the manual it says the sys is in destress maybe low on frion but checked high and low pressure and your right they are eqaul just a few pounds low like lest than 5 psi

 

It is possible that you are low enough that the low pressure switch turns off the compressor. It is not abnormal that it is 1 lb low as some freon can leak from the compressor shaft seal. Once the compressor starts, the high side should increase to 150-180 PSI and the low side should decrease to 35-40PSI.

Alan.

 

Jerryriged,

there is a program up date for the ACC automatic climate control module, if you don't have capability to program you will need to take to someone who can.

 

ok i will contact mb on the up date, I have fount 1 sensor in line it is a 4 wire plug in all my other cars i have had a low and high pressure switch but i don't see it on this one does one switch control it and i have fount it behind the front bumper. when i have chearged a/c in the past i just bypass the switch to get the compressore gone then hook back up afterwards can i do that on this car to check for bad switch and may psi is to low to kick on if not how would i do it thats for all you guys help also that have and will give your input

 

is there a way to clear the codes with out taking it to a person with a mb computer thanks for the help

 

Needs dye to test for leaks which is common with this model.Costs $250 for parts and labor at dealer as i was just told about mine.Good luck!