Hyster H360HD2, Service & Repair Manual

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FLYBACK DIODES
Some components induce current surges when they
are switched off. These surges can cause sparking
of mechanical contacts in switches and relays,
which results in premature erosion of these con-
tacts. Flyback diodes prevent these symptoms by
connecting the induced current surge to ground.
Always check functionality of a flyback diode when
a switch or relay has failed. In most cases a failed
diode will not conduct at all. Sometimes a failed di-
ode causes a short circuit.
Replacement diodes are integrated in connectors,
that attach the correct diode polarity to the wire
harnesses. Table 9 provides a complete listing of all
flyback diodes fitted.
CAN (CONTROLLER AREA NETWORK)
CAN bus is a standard for an electronic system that
allows communication between different controllers
without the need for a host computer.
The different controllers have their own controlled
network of sensors, actuators and control devices.
Functioning of these components cannot be influ-
enced by other controllers unless the programming
of a network controller specifically allows.
Each controller requires it’s own connection to volt-
age supply, to feed the controller and also to pro-
vide signals to the components that belong to the
controller network.
Without voltage supply a controller does not func-
tion.
Communication occurs through sending and receiv-
ing signals. Each signal contains amongst others a
code for the type of message (eg coolant tempera-
ture), the message itself (83°) and the ID of the con-
troller (ECM) that has sent the signal. Each con-
troller has been programmed to react only to cer-
tain messages from certain controllers. All other
messages are ignored.
Only two wires are required for communication:
The data wire and the data inverse wire. Integrity
of signal transfer is verified by comparing the re-
turn signal of the data inverse wire with the origi-
nal signal of the data wire.
The can bus system includes the following control-
lers:
Transmission controller
Hydraulic controller
Instrument cluster
Diagnostic connector*
Engine Control Module
(*)The diagnostic connector itself is not a controller.
Instead, the IFAK cable that leads to the lap top
computer contains the controller that will make
contact with the CAN bus system when plugged
into the diagnostic connector.
Table 9. Flyback Diodes
Connector Diode Description Tier III
Location
Tier IV
Location
Figure Item
CPS11 Relays [33,F] [32,F] Figure 10 and
Figure 11
59
CPS17 Main Power [25,A], [28,D] [24,A], [27,D] Figure 14 A 63
CPS34 Calibration [43,C] [52,C] Figure 14 78
CPS39 Lights [104,C], [56,I] [113,C], [65,I] Figure 14 79
CPS54 Backup [66,F] [75,F] Figure 10 and
Figure 11
67
CPS82 Horn [144,D] [153,D] Figure 15 97
CPS123 Cab Tilt Pump [89,F] [98,F] ---- ----
2200 SRM 1592 Electrical Schematic and System Description
13