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Introduction of the New Unimog Generation | Model Series 405
EAS
Tr
ansmission
•
Automated operation by means of pneumatic clutch actu-
ator PCA2 (Actros3 series production part) and short hy-
draulic circuit (dual master cylinder-central clutch release
bearing).
•
Two separate hydraulic circuits for optimal bleedability
and higher system availability. A short main circuit (both
operation types) between the dual master cylinder and
central clutch release bearing with separate reservoir. A
pedal circuit between the pedal master cylinder and dual
master cylinder. All lines have a continuously ascending
routing path to ensure the self-bleeding properties of the
system.
•
Hydraulic clutch pressure booster integrated in pedal cir-
cuit. Boosting is not required for automated operation.
•
Both hydraulic circuits are separately filled and bled (first
main circuit, then pedal circuit). This also reduces the
complexity for replacing individual components because
only the affected circuit has to be bled, if necessary.
•
Two reservoirs, one in the pedal circuit in the cab and one
in the main circuit behind the cab.
New features of the electronic automated gearshift
(EAS) system (code G48) for Unimog Euro VI vehicles
The technology of the automated clutch system has been
fully reworked but its operation is largely identical to that
of the predecessor model series. All of the functions of the
automated clutch system are combined in the transmission
control unit (TCM-Transmission Control Module). This means
that an additional clutch control unit is no longer required.
A folding clutch pedal is still installed for manual operation.
The operating medium DOT4+ (brake fluid) has remained the
same.
The release travel sensor on the central clutch release be-
aring is used to control the automated clutch engagement
process. In addition to the improved control quality, this ma-
kes it possible to compensate for tolerances e.g. due to small
quantities of air in the hydraulic fluid. The additional volume
required for this is held in reserve due to the increased stroke
of the dual master cylinder.
To take over the manual clutch function, the pedal must be
folded out (also possible while driving) and fully depressed
once. It is possible to switch to automated operation with the
vehicle at a standstill (ignition OFF no longer required). In ma-
nual mode, the vehicle can be operated like an EPS vehicle.
– This printout will not be recorded by the update service. Status: 03 / 2013 –
