A/C Components Controlled or Activated by Other Control Modules

A/C Components Controlled or Activated by Other Control Modules

• Various A/C system components are not controlled directly by the Climatronic Control Module (J255). For example the A/C Compressor Regulator Valve (N280) is controlled by the Vehicle Electrical System Control Module (J519). The data is exchanged via the data bus between the two control modules. Refer to the Vehicle Diagnostic Tester in the "Guided Fault Finding" function.

• The measured values of the different A/C system components are not evaluated directly by the Climatronic control module. Therefore, for example, the pressure signal from the A/C pressure/temperature sensor is evaluated by the Vehicle Electrical System Control Module and the measured values are sent via the data bus to the Climatronic Control Module. Refer to the Vehicle Diagnostic Tester in the "Guided Fault Finding" function and.

• A start-stop system is available for certain engines for this vehicle. The setting on the Climatronic Control Module, can prevent the stop function. If, for example, defrost is selected, the Stop Function is not possible or will be interrupted and the engine will start. The same applies in the case of heating and cooling. The difference between the target and actual temperature is greater than a specified value. Refer to the Vehicle Diagnostic Tester in the "Guided Fault Finding" function.

• Certain A/C system functions can be switched on and off via the MMI (Multi Media Interface) under the "A/C system" function in the "car"/"car systems" menu. The A/C system control can also be influenced via presettings in the MMI (Multi Media Interface) under the "A/C system" function in the "car"/"car systems" menu. Therefore, first check the presetting in the MMI in the case of a problem with these components. Refer to Infotainment/MMI operating instructions.