Engine Control System; Description - Manitowoc Grove TMS800E Service And Maintenance Manual

TMS800E SERVICE MANUAL

ENGINE CONTROL SYSTEM

Description

The engine control system is an electronically operated fuel
injection system that optimizes fuel economy and reduces
exhaust emissions. It accomplishes this by controlling the
torque and horsepower curve, air fuel control function,
engine high speed, low idle and road speed. The system
monitors critical engine temperatures and pressures, and will
log diagnostic faults when an abnormal operating condition
occurs. If an out of range condition exists, and engine derate
action is to be initiated, the operator will be alerted by an in-
cab warning light. The warning light will flash when out-of-
range conditions continue to get worse.
Functional Operation
Three key switch phases govern the operation of the engine
control system:
1. Ignition switch in the on position, engine diagnostics idle
switch off, engine not cranking or running.
2. Ignition switch in the on/start position, engine cranking.
3. Ignition switch in the on position, engine running.
With the ignition switch on, the diagnostic test switch off and
the engine not cranking or running, the electronic control
module (ECM) performs diagnostic and status operations. It
reads the logic inputs from the brake and cab switches and
analog inputs from sensors such as the engine coolant
temperature sensor and the manifold boost pressure sensor.
During this phase the data link is active and can be accessed
by the applicable service tools. The ECM runs the fuel lift
pump so the engine is ready to be started.
Additionally, when the key switch is turned on, the indicator
lights illuminate for approximately two seconds to verify they
are working and then go out. This is part of the normal
operation of the power-up sequence. However, if an active
fault is present, one of the lights will re-illuminate, determined
by the type of fault being sensed.
The electronic subsystem will also engage the starter lockout
relay to enable cranking. During the cranking phase, with the
ignition switch in the start position, the ECM commands all of
the fuel needed to start the engine. There is no need to use
the throttle pedal while cranking the engine.
While the engine is cranking the ECM is performing
additional diagnostic and status operations. An active fault
causes a combination of the three indicator lamps (engine
warning, engine stop, and malfunction indicator lamp (MIL))
to illuminate and remain lit. Which lamp is illuminated
depends on the severity of the fault.
Normal operation occurs when the engine is running.
At this point the starter lockout relay will be disengaged.
GROVE
Engine Control System Switches and Indicator Lights
Engine Idle/Increment-Decrement Switch
The Engine Diagnostic/Idle Switch, located on the left side of
the carrier cab console, is a two position maintained on/off
rocker switch used to access the engine fault codes or
enable the control of the engine idle speed. Default idle
speed will resume after each engine shutdown (70 seconds)
and restart.
Diagnostic function - With the Ignition Switch in the RUN
position and the engine off, press the top of the Engine
Diagnostic/Speed Control Switch to view the engine fault
codes. Fault codes will be flashed out using the Engine Stop
Indicator Lamp and the Engine Warning Indicator Lamp. If
there is more than one active engine fault code, use the
Increment/Decrement Switch to toggle forward and
backward through the fault codes. If there are no engine fault
codes, both Engine Stop and Engine warning Lamps will be
on solid.
Engine Idle Function - With the engine running and the
bottom of the Engine Diagnostic/Idle Switch activated, the
engine idle may be slightly increased or decreased by using
the Increment/Decrement Switch.
Increment/Decrement Switch (Superstructure Cab)
The Increment/Decrement Switch is a three position
momentary rocker switch with center maintained position
being off. There is one located in the carrier cab and one in
the superstructure cab.
In the carrier cab, use this switch in conjunction with the
Engine Diagnostic/Idle switch as describe directly above.
In the superstructure cab, this switch is used to adjust engine
RPM. Quickly press the top of the switch (+) once to go to full
engine RPM; quickly press the bottom of the switch (-) once
to return to low engine idle. If the engine speed is below the
maximum RPM setting, pressing and holding the top of the
switch (+) will cause the engine RPM to slowly increase;
release the switch when the desired RPM is attained. If the
engine speed is above the minimum RPM setting, pressing
and holding the bottom of the switch (-) will cause the engine
RPM to slowly decrease; release the switch when the
desired RPM is attained.
Note: The engine RPM will be based on which ever device,
the foot pedal throttle or the increment/decrement switch, is
requesting the greater RPM.
Engine Regeneration Start Switch
This switch, located on the left side of the front console in the
carrier cab, enables the operator to initiate a stationary
exhaust regeneration is required and when engine RPM is
greater than zero. The switch must be cycled on and off to
initiate regeneration. The throttle, clutch and brake pedals
must also be released. The engine will automatically change
Published 01-29-2014, Control # 496-00
POWER TRAIN
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