E320 Climate Control - Help!
 

The A/C blows cold on the passenger side but hot on the drivers side no matter what temp I set the climate control unit to. Anyone have any ideas on thi. Car is a 96 E320 Sedan.

Your a\c system may low on freon or dual mono valve (heater valve) problem do a search.......on this one.

Tap on the monovalve, it might be sticking.

If you have the digital display climate control module there are some tests you can perform.

I have exactly the same problem ('97 E420 w210)

>If you have the digital display climate control module there are some tests you can perform.
Can you please describe what kind of tests and how to perform them (If you have this info)

Diagnostics
 

See here:

http://www.continentalimports.com/ser_ic60046.html

http://www.continentalimports.com/ser_ic40142.html


Or here:

http://pages.prodigy.net/jforgione/MB_S500.html

If you have problem with hot air on one or both sides pay attention to the third and fourth values in chart 1, if they are high when running the AC it means the duovalve isn't closing the flow through the heater cores.

I just checked everything

#3 - Heater Core temp (Left)
#4 - Heater Core temp (Right)

after about 10 minutes
#3 = 20 and #4 = 11

and

after about 15 minutes
#3 = 15 and #4 = 8


are these normal or should I look into replacing Mono valve?


Rest of the values:
#1 = 29
#2 = 63
#5 = 20
#6 = 112
#7 = 09
#8 = 43
#9 = 01
#10 = 2.0
#11 = 2.9
#12 = 4.3
#20 = 7.9
#21 = 06
#22 = 00
#23 = 00
#24 = 13.3
#40 = 71
#41 = 25
#42 = 00
#43 = 152

Based on the value of #7 I think you are low on refrigerant. Nine bar is too low for the refrigerant pressure with the system running - should be more in the range of the middle teens, depending on temperature. On the 210 chassis we've seen previous posts where low refrigerant caused one side of the car to cool and the other not.

- JimY

Thank you I will double check and add refrigerant.

I just did the flaps test and it looks like right and left diverter flaps didn't operate. Could someone provide schematics (how to reach them and check / replace (part numbers would help)).

Could this be related to the recent blow motor change that was done by my mechanic? He replaced blower and regulator, however did not install the plastic pad (he said that it was not neccessary).

I have 97 E420 and blower had to be replaced with the regulator because the one I had would not fit the new blower model.