Nissan Versa Sedan Service ManualEngine » Engine control system (EC)
Air conditioning cut control
Air conditioning cut control
AIR CONDITIONING CUT CONTROL : System Diagram
AIR CONDITIONING CUT CONTROL : System Description
INPUT/OUTPUT SIGNAL CHART
| Sensor | Input signal to ECM | ECM function | Actuator |
| Crankshaft position sensor (POS) Camshaft position sensor (PHASE) | Engine speed*1 Piston position | A/C compressor request signal | IPDM E/R ↓ Air conditioner relay ↓ Compressor |
| Engine coolant temperature sensor | Engine coolant temperature | ||
| Accelerator pedal position sensor | Accelerator pedal position | ||
| Battery | Battery voltage*1 | ||
| Refrigerant pressure sensor | Refrigerant pressure | ||
| EPS control unit | EPS operation signal*2 | ||
| Combination meter | Vehicle speed signal*2 | ||
| BCM | A/C ON signal*2 Blower fan signal*2 |
*1: ECM determines the start signal status by the signals of engine speed and battery voltage.
*2: This signal is sent to the ECM through CAN communication line.
SYSTEM DESCRIPTION
This system improves engine operation when the air conditioner is used.
Under the following conditions, the air conditioner is turned off.
- When the accelerator pedal is fully depressed.
- When cranking the engine.
- At high engine speeds.
- When the engine coolant temperature becomes excessively high.
- When operating power steering during low engine speed or low vehicle speed.
- When engine speed is excessively low.
- When refrigerant pressure is excessively low or high.
Can communication
CAN COMMUNICATION : System Description
CAN (Controller Area Network) is a serial communication line for real time application. It is an onvehicle multiplex communication line with high data communication speed and excellent error detection ability. Many electronic control units are equipped onto a vehicle, and each control unit shares information and links with other control units during operation (not independent). In CAN communication, control units are connected with 2 communication lines (CAN H line, CAN L line) allowing a high rate of information transmission with less wiring.
Each control unit transmits/receives data but selectively reads required data only.