2003 E320 W211
This is a friend's car. I am trying to figure out what the problem is with the A/C.
The "A/C Off" button's red light comes on. If you push the button the light flashes a few times then stays on.
The compressor pulley appears to be engaged. The center of the pulley is rotating.
The HVAC unit is set to auto with both temp. selectors set to 60 degrees.
Thinking it was low on refrigerant, I hooked up a fill hose that has a gauge on it and the gauge read 80psi. That seems high. The markings on the gauge face indicated that at the ambient temp (50 degrees) the pressure should have been around 25 psi.

Where to look next ?
I have found some mention of self diagnosis through the HVAC controls, but this car does not have the highline controls with the LCD screen.


Thanks,
Greg

__________________
Greg
2012 S350 BlueTEC 4Matic
2007 ML 320 CDI
2007 Leisure Travel Serenity
2006 Sprinter 432k
2005 E320 CDI
1998 SLK230 (teal)
1998 SLK230 (silver)
1996 E300D 99k, 30k on WVO
Previous:
1983 240D, on WVO
1982 300D, on WVO
1983 300CD, on WVO
1986 300SDL 237k, 25k on WVO (Deerslayer)
1991 350SDL 249k, 56k on WVO - Retired to a car spa in Phoenix
1983 380 SEC w/603 diesel, 8k on WVO
1996 E300D 351k, 177k on WVO