Features (TB48 Engine Models)
CAN COMMUNICATION SYSTEM DESCRIPTION
CAN (Controller Area Network) is a serial communication line for real time application. It is an on-vehicle mul-
tiplex 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 wir-
ing. Each control unit transmits/receives data but selectively reads required data only.
SYSTEM CONSTRUCTION
Magnet clutch control
When A/C switch is pressed, turn fan control dial to ON or set mode control dial to DEF position, A/C auto
amp. inputs compressor ON signal to ECM.
ECM judges whether compressor can be turned ON, based on each sensor status (refrigerant pressure sen-
sor signal, throttle angle, etc.).
When sending compressor ON signal to ECM from A/C auto amp., ECM simultaneously sends compressor
feedback signal to uni®ed meter C/U via CAN communication line.
Uni®ed meter control unit sends compressor feedback signal to A/C auto amp. Then, A/C auto amp. uses input
compressor feedback signal to control air inlet.
RHA408I
DESCRIPTIONAUTO
HA-4002