W140 Climate Control

[Neville Stebbings]

Can anyone supply a detailed description of the function of the climate control system, in particular the airflow control? My air-con will only blow cool air out of the face vents. If the system is set to warm the cabin, it will blow warm air out of the screen and footwell vents. If the system is set to cool the cabin, there is no airflow at all out of the screen or footwell vents. The dealer says that he can't find any fault with the system, but I don't think this is right. Any advice gratefully received.

 

[markku]

A/c

There are some detailed AC testing instructions in the pages of Jim Forgione: http://pages.prodigy.net/jforgione/MB_AAC.html

 

[Neville Stebbings]

thanks for the advice. The info. is very good, but my climate control system is of a different type. The car was first registered in Jan 1997.

 

[markku]

A/C part two

How about this: http://www.continentalimports.com/ser_ic40142.html

 

[Neville Stebbings]

Thanks! This looks as though it should help.

 

[markku]

Automatic A/C

My air-con will only blow cool air out of the face vents. If the system is set to warm the cabin, it will blow warm air out of the screen and footwell vents. If the system is set to cool the cabin, there is no airflow at all out of the screen or footwell vents.

Looking at your description more carefully I think your A/C is working perfectly, it is exactly how an auto A/C should work. Auto A/C has a mind of its own and tries to do cooling and heating as MB engineers intended. I have given up and left everything in Auto and default values ( push up and down arrows simultaneously ). Same Auto-settings during the summer and winter, no tweaking.

Just enjoy.