Mercedes-Benz Forum banner

1 - 2 of 2 Posts

·
Registered
Joined
·
1 Posts
Discussion Starter #1
So I have this issue.

First, the unit was blowing hot air. After checking the manual, doing some checks per the 83 section, I discovered either the pressure sensor was either bad or there was not any R134a. So, thinking of the easier fix, I added refrigerant. A/C was now blowing cold air... through the defrost and lateral vents. Even with it set to 'normal' the air was not blowing through the central and lateral vents, only through defrost and lateral vents.

I set the temp to 'min' on the temperature dial, put it on 'bi-level' seeing what that would do. Same thing. Only air blowing through lateral and defrost vents.

Some further checking was done, and it was discovered the green/yellow tube from the top of Y7, did not have a vacuum. None at all. So this will explain why none of the vents are doing anything.

So, where does the green/yellow tube from the top of Y7 go and how much vacuum should there be?
 

·
Registered
'95 E300 DIESEL, '91 600SEL, '92 600SEL
Joined
·
17,405 Posts
Before going deep dash diving, make sure that the yellow check valves next to the brake booster are working and properly connected.

These check valves have a direct impact on the vent operation.
 
1 - 2 of 2 Posts
Top