64 50... A/C performance test

Observe the following conditions prior to the A/C performance test: 

1. Connect BMW diagnosis system. Check of the fault memory (no faults in the fault memory).
2. Attach a thermometer with separate display device to the head restraint and route the display device wiring out of the passenger compartment outward.
3. Perform the test in a suitable workshop area with an ambient temperature above 18° C.
4. Vehicle temperature should be approximately the same as the ambient temperature in the workshop.
5. Engine must be at operating temperature.

Heat passenger compartment: 

• "A/C button" is not activated during the heating process
• Close all windows and doors.
• Set air recirculation function.
• Select air distribution mode for footwell and defrosting.
• On vehicles with CID  : In A/C menu (CID) in Air distribution index tab: select 100 % footwell for driver and front passenger and 100 % defrosting for driver (this applies here to driver and front passenger)
• Maximum temperature setting
• Maximum blower speed
• Start engine

Cool down passenger compartment: 

Turn on air conditioning compressor with "A/C button" at a vehicle interior temperature of 45 °C (measured at the head restraint).

On vehicles with MAX-AC button: 

• Activation of MAX-AC (= maximum cooling power)

On vehicles without MAX-AC button: 

• Set maximum cooling power by means of following steps:
  • Setting minimum temperature
  • Blower setting maximum
  • Stratification maximum cold (4 blue bars)
  • Only ventilation open
  • Close remaining flaps (air outlet only from center fresh air grille, left and right)

After 5 minutes measure both ventilation temperatures with a thermometer at the same time (fresh air grille center, left and right). The measured temperature must be ≤ 16° C and the difference between right and left may not be greater than 2° C.

If one or both temperature specifications is not reached DRAIN OFF  heating and air conditioning system. Measure the amount of refrigerant drawn off and compare with the NOMINAL FILL AMOUNT .

Check whether refrigerant loss is present:

• If there is a PERMISSIBLE LOSS  of refrigerant, fill the refrigerant circuit with the NOMINAL FILL AMOUNT .
• If there is an IMPERMISSIBLE LOSS  of refrigerant, CHECK THE REFRIGERANT CIRCUIT FOR TIGHTNESS . After rectifying the leak, fill the refrigerant circuit with the NOMINAL FILL AMOUNT .