Can−Bus Communications; Electrical Drawings - Toro Groundsmaster 5900 Series Service Manual

24 Volt System (continued)
CAN−bus Communications

Electrical Drawings

Electrical System: Electrical System Operation
In normal operating mode, the radiator fans will not operate until the engine
coolant reaches the minimum temperature. Once the minimum coolant
temperature is reached, the fans will begin to turn at low speed in the forward
direction (pulling outside air through the radiator). The Hydraulic oil cooler fans
will always run when the engine is running. They will also run at a low speed in
the forward direction (pulling outside air through the oil cooler) until the minimum
oil temperature. Fan speed will increase if the coolant/hydraulic oil temperature
increases. If maximum fan speed in the forward direction does not maintain the
coolant/hydraulic oil temperature at its desired temperature, the fans will reverse
direction and operate at maximum speed for 6 seconds. Fan reverse cycles can
occur at one minute intervals as needed.
Irregardless of coolant temperature, the radiator fans are programmed to reverse
periodically to clean debris from the radiator screen.
Additional information about electrical components in the 24 VDC system is
included in the Component Testing and Service and Repairs sections of this
chapter.
The two (2) TEC controllers, the Yanmar Engine Controller and the InfoCenter
Display used on the Groundsmaster 5900 and 5910 communicate with each
other on a Controller Area Network (CAN) bus system. Using this network
allows the traction unit to fully integrate all the different electrical components of
the tractor and bring them together as one. The CAN bus system reduces the
number of electrical components and connections used on the machine and
allows the number of wires in the wire harness to be significantly reduced. The
integration of electrical functions also allows the Info- Center Display to assist
with electrical system diagnostics.
Each of the components that is controlled by the CAN bus link only needs four
(4) wires to operate and communicate to the system: CAN High, CAN Low,
power and ground. The key switch needs to be in the RUN or START position
for the components on the network to be activated.
Two (2) specially designed, twisted wires form the CAN bus. These wires provide
the data pathways between the components on the network. The engineering
term for these cables are CAN High and CAN Low. The bus wires for the 12
VDC circuits are black/white and red/ white. At the end of the twisted pair of bus
cables is a 120 ohm termination resistor.
The termination resistor at the end of the bus wires is required for
proper electrical system operation.
The electrical schematic and wire harness drawings for the Groundsmaster 5900
and 5910 are located in
IMPORTANT
Appendix A (page A–1).
Page 6–8 Groundsmaster ® 5900 & 5910
16227SL Rev B