SRT45 Off-Highway Truck
3-28
Safety, Operation and Maintenance Manual
3.13.2 Introduction and operation
(1) Electronic Control Unit (ECU) – The ECU
contains an electronic microcomputer.It
receives information in the form of electronic
signals from switches and sensors, processes
the information, and sends electronic signals
to the appropriate solenoids which control the
transmission.
(2) Control box -- contains VIM and ECU.
(3) Gear shift selector -- the shift selector is
a remote mounted lever type. The gear shift
selector is connected to the ECU by a wiring
harness. The shift lever has 6 forward ranges
and 1 reverse ranges, as well as a neutral
position.
The shift selector has a single digit LED
display, which during normal operation
will display the gear selected. Diagnostic
information can be displayed on the single
digit LED display by pressing the diagnostic
display button. There is a hold override button
that must be pressed when shifting between R,
N and D. The hold override button is released
when desired selector position is reached. The
selector lever can move freely between D and
the number ranges without pressing the hold
override button. (Refer to fig.3-17)
WARNING
Do not allow the vehicle to coast in
Neutral. This practice can result in
severe transmission damage.
The transmission upshifts and downshifts
automatically between first range and the
highest range selected on the range selector
in direct response to throttle position, engine
speed and transmission output speed.
When Reverse is selected the reverse alarm
sounds and the reverse indicator illuminates
at the rear of the vehicle. This feature warns
personnel to the immediate rear of the vehicle
Fig 3.17
MODE
R
N
D
5
4
3
2
1
R
Controls and Operating
