870101 Checking Function of Air Conditioner
WM 870101 Checking function of air conditioner
Checking operation of air conditioner
General information
Information
- The air outlet temperatures at the centre nozzle of the dashboard and the high pressure in the air conditioner must not exceed the specified tolerance ranges after an operating time of seven minutes.
Procedure and general test prerequisites
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.
1. Connect the air conditioning service unit. =>
2. Measure outside temperature with a thermometer.
3. Open all air exhaust nozzles on the dashboard (if necessary direct the blower near the test person).
4. Insert sensor of the temperature measuring device approx. 4 cm centrally into the left-hand centre nozzle.
5. Check stopwatch and visual contact with the relevant temperature and pressure on the air conditioning service unit.
6. Switch on ignition.
7. Open driver's and passenger's side windows and close sunroof.
8. Set the temperature for both sides to maximum cooling (LO appears in the display).
Information
- With a 4-zone-air conditioner, the rear air conditioner must also be set to maximum cooling for both sides (LO) (if necessary, use the MONO function) and the rear air exhaust nozzles left open. To activate the MONO function, the AUTO -adjusting lever of the front air conditioning control must be pressed longer than two seconds (MONO appears in the display).
9. Set maximum blower speed.
10. Start engine and allow to run at idle speed (do not rev engine during or after starting.)
11. Operate air conditioner for five minutes at idle speed.
12. Bring engine speed up to 2000 rpm and maintain it there. Start the time measurement immediately.
13. Note centre nozzle temperature and pressure values after two minutes.
14. Compare values (centre nozzle temperature and pressure readings) with the specified tolerances.
Information
- If the specified nominal values are not reached, the air conditioner must be checked for leaks and repaired.
Technical values
Centre nozzle temperature as a function of outside temperature: 2-zone air conditioning
High pressure in refrigerant circuit as a function of outside temperature: 2-zone air conditioning
Centre nozzle temperature as a function of outside temperature: 4-zone air conditioning
High pressure in refrigerant circuit as a function of outside temperature: 4-zone air conditioning
Tools and materials
