Hydraulic Gauges, Warning Indicators, And Message Displays - freightliner WALK-IN VAN CHASSIS Operator's Manual

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04/15/2011
1. Transmission Control Module
2. Bulkhead Connectors
3. Hybrid Control Module
Fig. 16.9, Floor Panel Access
Hydraulic Gauges, Warning
Indicators, and Message
Displays
Gauges
The hybrid performance gauge and the state-of-
charge (SOC) gauge are two hydraulic hybrid system
gauges located in the instrument panel. See
Fig. 16.10.
Hybrid Performance Gauge
The hybrid performance gauge displays how effi-
ciently the vehicle is being driven. The green ECON
area, which is the target range, represents when the
vehicle is operating in the most economical range.
When normal acceleration and braking occur, brake
energy recovery maintains a high state-of-charge in
the accumulator for maximum hydraulic hybrid drive
performance.
The red BRAKE area indicates an aggressive brak-
ing occurrence. Aggressive braking uses more fric-
tion braking than regenerative braking to slow the
vehicle, which results in less energy captured for
storage in the accumulator.
The red ACCEL area indicates when the accelerator
is fully depressed, which depletes the energy stored
3
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Hydraulic Hybrid
in the accumulator in two ways. First, the engine
would restart sooner than normal, and reduce the
amount of engine-off time. Second, if the engine is
already running, the engine's energy is used in a
less efficient manner to further accelerate the ve-
hicle.
If the hybrid performance gauge does not remain
within the ECON area, regardless of how efficiently
the brakes or accelerator are applied during opera-
tion, contact a certified hydraulic hybrid drive service
technician to determine if there is a problem with the
gauge or the system.
State-of-Charge (SOC) Gauge
The SOC gauge displays the available fluid pressure
(energy) in the accumulator for use by the hydraulic
hybrid drive system.
Slower vehicle speeds require less energy use by
the hydraulic hybrid drive system to propel the ve-
hicle, allowing it to maintain a higher percentage of
stored fluid pressure in the accumulator.
The state-of-charge can also be maintained through
normal braking, where brake energy recovery is en-
abled, allowing the rear wheels to drive the second-
ary pump to pressurize the accumulator. Light to
moderate braking will increase the state-of-charge
more for a given event.
The higher the state-of-charge, the more energy
there is to propel the vehicle with the hydraulic hybrid
drive system rather than the engine. This results in
fuel savings and less wear on the engine.
The state-of-charge can also be increased by ag-
gressive acceleration. However, this type of increase
in the state-of-charge will decrease fuel economy
and should be avoided.
If the percentage on the gauge remains in the red
area regardless of how efficiently the vehicle is oper-
ated, contact a certified hydraulic hybrid drive service
technician to determine if there is a problem with the
gauge or the system.
Warning and Indicator Lights
The warning and indicator lights are located in the
instrument panel and contain all of the standard and
optional warning and indicator lights. See
When the ignition is turned to the ON position, all
indicators will illuminate for a required self-test.
Fig. 16.11.
16.6