A/C Compressor Activation

Function

The A/C compressor is controlled as follows:

• Operation of the air conditioning button
  

• Sending the request via K-CAN to the central gateway (junction box)
  

• Passing on the request request via PT-CAN to the DDE control module
  

• Setting of the operating mode ”Air conditioning on” by the DDE control module
  

• Then transfer of the request from the DDE control module via PT CAN to the gateway (junction box)
  

• Forwarding of the request from the central gateway to the electrical control valve on the air conditioning compressor
  

• Activation of the air conditioning compressor
  

The A/C compressor is switched off in precisely the same way.

This procedure ensures that at the time the air conditioning compressor is switched on, the engine has sufficient power reserves. Activation of the A/C compressor does not bring about a dip in engine speed.

Diagnosis

In the event of a fault, the entire signal path must be checked.