Operation and maintenance manual
3-18
If the vehicle is approaching an overspeed condition, the transmission performs an
upshift at an engine speed of 2 500 rev/min to the next highest gear to decrease the
engine speed, whether in manual or automatic mode. If 6th gear is already selected,
the retarder is automatically engaged at 2600 rev/min to decrease the engine speed
irrespective of the accelerator position. The retarder is disengaged at 2450 rev/min.
A fault code will be displayed and recorded by the TCU. If the oil temperature reaches
150° C (302° F) the retarder is disengaged and a fault code will be displayed and
recorded by the TCU.
Engine
Electronic Foot Pedal
The electronic foot pedal provides an electrical signal to the engine's fuel control
system in proportion to the degree of pedal actuation.
Note: The engine MUST be started with foot 'OFF' the electronic foot pedal.
Detroit Diesel Electronic Control (DDEC)
This machine is equipped with the Detroit Diesel Electronic Control (DDEC)
which continually monitors the engine and warns the operator when a problem
develops. The DDEC system also takes action to prevent damage to the engine
and, provides the serviceman with diagnostic capabilities so that problems can
be corrected quickly and easily.
WARNING
Before any welding is done on a machine equipped with the DDEC system,
disconnect the following in this order: Battery earth cable, battery supply
cable, alternator earth cables, alternator supply cables, body hydraulics
joystick, transmission (Est-37) connector, ECM interface harness connector
(30 pin RHS), ECM power harness connector (5 pin RHS), ECM sensor
harness connector (30 pin LHS) and ECM engine to transmission datalink
connector (6 pin RHS). Turn off battery master switch before disconnecting
any components.
After welding connect all of the above in the reverse order.
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