Communication between air conditioner and injection computer
The injection ECU authorizes the compressor to turn on based on the power the compressor draws and the refrigerant pressure in the circuit.
Information used for the air conditioning system is transmitted over the multiplex network
- pin B H3 CAN channel H of the multiplex network (CECBS);
- pin B H4 channel CAN L multiplex network (CECBS).
When the air conditioner switch is pressed, the air conditioner control panel requests permission to turn on the compressor. The injection ECU decides whether or not to turn on the compressor, controls the engine cooling fan and sets the appropriate fast idle speed, which is 700 min'.
Attention! The refrigerant pressure and power input are never 0, whether the compressor is on or off.
A/C Compressor Activation Strategy
In some engine operating modes, the injection computer prohibits the activation of the air conditioning compressor.
Engine start strategy
The operation of the air conditioning compressor is prohibited after the engine is lowered for 20 seconds.
Overheat protection strategy
The air conditioning compressor does not turn on if the coolant temperature is above 115°C.