Procedure And General Requirements For Testing

Information 

• The safety regulations must be observed during all work on the refrigerant system!  → 8X00IN SAFETY REGULATIONS FOR WORKING ON AIR-CONDITIONED VEHICLES AND DEALING WITH REFRIGERANT R134A , → 8X00IN SAFETY REGULATIONS FOR EXTRACTION AND FILLING SYSTEMS .

Information 

• If the specified nominal values are not reached, the air conditioning must be checked for leaks and repaired  .

Information 

• Check condensed water drain tubes: Must not be blocked by wax or underbody protection or otherwise dirty. Condensate must be able to drain away freely  .
• Check fresh-air intake system: Water must not be allowed to run into the air conditioner. Must be completely dirt-free  .
• Check that there is sufficient ventilation in the outside-temperature sensor area  .
• Do not allow heat from the warm engine to build up near the outside-temperature sensor  .
• Check particle filter: Must be dry and not excessively dirty  .
• Condenser must be dirt-free  .
• Make sure that all servo motors/flaps move to their end positions  .
• Switch on MONO mode or SYNC mode using the button on the front air conditioning control panel  .

1. Connect air conditioning service unit. → 870317 DRAINING AND FILLING REFRIGERANT .
2. Measure outside temperature with a thermometer.
3. Open all air outlet vents on the dashboard, center console and B-pillar (direct the blower near the test person if necessary).
4. Insert sensor of the temperature measuring device approx. 4 cm into the middle of the left center vent  .
5. Check stopwatch and keep an eye on the relevant temperature and high pressure on the air conditioning service unit.
6. Switch on ignition.
7. Hybrid vehicles: Check battery temperature of HV battery. Temperature must be < 35 °C  .
8. Open driver's and passenger's side windows and close sliding roof.
9. Press A/C Max button.
10. Start the engine and leave it running at idlespeed (do not rev engine unnecessarily after starting!).

    Hybrid vehicles:  Establish driving readiness (with or without combustion engine running).

11. Operate air conditioning for five minutes at idle speed.
12. Increase engine speed  depending on engine type and maintain a constant engine speed for two minutes  . Start the time measurement immediately.
    1. 12.1. Increase engine speed on V6 petrol vehicles to 2, 000 rpm  .
    2. 12.2. Increase engine speed on V8 petrol vehicles to 1, 900 rpm  .
    3. 12.3. Increase engine speed on diesel vehicles to 1, 500 rpm  .
    4. 12.4. Hybrid vehicles:  Not necessary. Continue with Step 13.
13. Note center vent temperature and pressure values after two minutes.
14. Compare values (center vent temperature and pressure values) with the specified tolerances.