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Identifying Malfunctions In Deviation From Specified Value (Required Cooling Output Of Heating And A/C System Not Achieved): Notes

-- In the "read measured values" function, select the display group with the measured values for the A/C compressor activation and the refrigerant circuit pressure. Use the Vehicle Diagnostic Tester in the "Guided Fault Finding"  function.-- Repeat the cooling output test. Refer to COOLING OUTPUT, CHECKING .-- During the cooling output test, pay attention to the display for the compressor actuation.-- Is the activation of the A/C Compressor Regulator Valve -N280- switched off during the cooling output test (is the specified and/or the actual current less than 0.35 A)?
↓ Yes ↓ ↓ No ↓
Continuation refer to TEST CONTINUATION "THE A/C COMPRESSOR ACTUATION IS SWITCHED OFF" . The A/C compressor activation is switched off.
  • Did the pressure in refrigerant circuit increase during the cooling output test?
  ↓ Yes ↓ ↓ No ↓
  Continuation CONTINUATION OF TEST: "PRESSURE IN REFRIGERANT CIRCUIT INCREASES" . Increase in refrigerant circuit pressure. -- Check one more time if the compressor shaft is actually being driven and if the A/C Compressor Regulator Valve -N280- is really being actuated.-- If the A/C compressor is being driven and the A/C Compressor Regulator Valve -N280- is activated, bring the vehicle to a workshop that has the necessary tools and in which the work can be performed by qualified personnel. Refer to A/C SYSTEM, GENERAL INFORMATION or LAWS AND REGULATIONS . -- Bring the detected problems to the attention of the workshop.