BMW X5: Air Conditioner Test (R 134A)
Before A/C efficiency test, satisfy following conditions:
1. Provide a MoDiC or DIS. Safeguard electrical system integrity by checking the fault memory (no faults in the fault memory).
2. Provide a thermometer with separate gauge.
3. Perform the test in a suitable work bay with an ambient temperature between 20 ºC and 30 ºC.
Re 1:
Connect MoDiC or DIS to car and display evaporator temperature.
Re 2:
Position a thermometer with a separate gauge approx. 5 cm below the roof liner at the height of the B-pillar.
Lay gauge outwards out of vehicle interior.
Re 3:
Heating up vehicle interior:
- A/C button is not activated during heating up.
- Close all windows and doors.
- Set recirculated air mode.
- Select air distribution mode for footwell and defrosting.
- Maximum temperature setting.
- Maximum fan stage.
- Run engine at approx. 2000 RPM until operating temperature is reached, then idle speed.
A/C efficiency test:
Turn on A/C compressor at a vehicle interior temperature of 50 ºC.
After 3-4 minutes, the evaporator sensor temperature must be > or = 15 ºC.
Draw off A/C system if this temperature is not reached. Measure amount of refrigerant drawn off.
If drawn-off quantity does not correspond to specified fill quantity : supplement refrigerant and repeat test.
If fill quantity is correct, continue troubleshooting by pressure measurement.
