Volkswagen Passat 1995 Official Factory Repair Manual page 4200

A/C refrigerant system, troubleshooting
http://ebahn.bentleypublishers.com/vw/servlet/Display?action=Goto&type=repair&id=VW.B4.HA01.87.6
A/C refrigerant system pressures,
checking
Check A/C refrigerant system pressures using
these three tests:
1 - Air temperature drop from center instrument
panel outlet (A/C system cooling performance)
2 - A/C system high pressure
3 - A/C system low pressure
The combined results of all three steps
determine which part of the A/C system is
causing the problem, see table
Test conditions
A/C refrigerant system fully charged; discharge,
evacuate and recharge system if necessary
Condenser and radiator clean and free of
obstructions (spray clean if necessary)
Air distribution can be adjusted correctly using
control knobs (all air distribution flaps reach end
positions)
Wiring OK per wiring diagram
Outside (ambient) air temperature between 20-
30 C (68-86 F)
Drive belts for A/C compressor and Generator
in good condition and properly tensioned
Page 3 of 10
87-106
Page 87-110 .
12/7/2004