A3 | Drive control (CPC) control unit |
A4 | Engine management control unit (MCM) |
B640 | Coolant pump rpm sensor |
CAN 4 | Drive train CAN |
Y616 | Fan clutch solenoid valve |
Y616 b1 | Fan rpm sensor |
Y631 | Coolant pump solenoid valve |
Z4 | Drive CAN bus star point |
a | Coolant pump rotational speed, signal |
b | Coolant pump, actuation |
c | Fan clutch rotational speed, signal |
d | Fan clutch, actuation |
e | Coolant temperature, signal |
f | Charge air temperature, signal |
g | Engine speed, signal |
h | Secondary coolant-retarder, status (with secondary coolant-retarder only) |
G20.00-3122-76
General
Engine cooling heat management optimizes the efficiency of the engine and thus reduces fuel consumption. This is achieved by specifically actuating the following components as required:
Coolant pump
Fan clutch
Regulation of the coolant pump reduces the coolant throughput through the engine to the extent necessary in the respective operating status. The radiator's cooling air throughput is additionally regulated by the fan clutch depending on the operating status.
Coolant pump magnetic clutch (viscous) regulation
The coolant pump's delivery rate is continuously variable. The magnetic clutch (viscous) is actuated by the engine management control unit (MCM) (A4) using a pulse width modulated signal. To do this, the engine management control unit (MCM) (A4) evaluates the following information:
Coolant temperature
Engine speed
Engine throttle condition
Coolant pump rotational speed (registered by the coolant pump rpm sensor (B640))
Compressor operating status (active/idle)
Secondary coolant-retarder operating status (with secondary coolant-retarder only)
Depending on the listed information, the engine management control unit (MCM) (A4) calculates the corresponding controlled variable for actuating the coolant pump solenoid valve (Y631).
On vehicles with secondary coolant-retarder, the coolant pump is actuated with full power in secondary coolant-retarder braking mode to achieve the maximum braking effect of the secondary coolant-retarder.
Electromagnetic viscous fan clutch regulation
The electromagnetic viscous fan clutch delivery rate is continuously variable. Actuation is carried out by the engine management control unit (MCM) (A4) using a pulse width modulated signal.
To do this, the engine management control unit (MCM) (A4) evaluates the following information:
Coolant temperature
Engine oil temperature
Charge air temperature
Engine speed
Fan speed (registered by the fan rpm sensor (Y616 b1))
Secondary coolant-retarder operating status (with secondary coolant-retarder only)
Depending on the listed information, the engine management control unit (MCM) (A4) calculates the controlled variable for actuating the fan clutch solenoid valve (Y616).
Engine cooling system thermal management, overall network | |||
Drive control (CPC) control unit, component description | A3 | ||
Engine management (MCM) control unit, component description | A4 | ||
Coolant pump component description | B640, Y631 | ||
Component description for the electromagnetic viscous coupling | Y616, Y616 b1 |