Ultrashift Diagnostics - freightliner cascadia Driver Manual

If the transmission does not upshift quickly enough
after power-up or a load change, begin the shift
manually. The UltraShift DM TCU will learn the new
load-based shift conditions after three or four shifts.
If the gear requested is unavailable, a tone will
sound. An unavailable request to upshift is not stored
in memory. The upshift must be requested again.
Downshifting
NOTE: The driver can manually downshift at
any time, even when the slide switch is set to
AUTO mode.
To request a downshift with the transmission in drive
or low, push the control lever down (away from you).
If the gear is available, the transmission downshifts
and the new gear displays on the gear indicator. Skip
shifts are available while downshifting.
For best engine braking, select low while moving. In
low, downshifts are performed at higher rpm than in
drive.
IMPORTANT: If the engine is approaching over-
speed, the UltraShift DM TCU will override the
current gear setting and upshift to prevent en-
gine damage.
If the gear requested is unavailable, a tone will
sound. An unavailable request to downshift is not
stored in memory. The downshift must be requested
again.
When coasting to a stop, the UltraShift DM TCU may
not finish the downshift until the driver presses down
on the throttle pedal again.
IMPORTANT: A downshift request can never
result in a shift into neutral, even if the vehicle is
in the drive position in the lowest possible gear.
Before starting down a hill, slow down. Downshift to
a speed that you can control without hard pressure
on the service brakes.
Before entering a curve, slow down to a safe speed.
Downshift if necessary. This lets you use some
power through the curve to help the vehicle be more
stable on the turn. It also allows you to regain speed
faster as you come out of the curve.
Automated Transmissions

Ultrashift Diagnostics

Clutch Protection Fault
Excessive clutch slippage creates heat and reduces
the life of the clutch. These are some conditions
which lead to clutch abuse:
•
Using the throttle to hold the vehicle on a
grade
•
Starting the vehicle in too high a gear
•
Overloading the vehicle
•
Using high idle with the vehicle in gear
The UltraShift DM TCU is programmed to prevent
clutch abuse. When the clutch overheats, the follow-
ing alerts take place:
•
The TRANS TEMP light comes on
•
The current gear indicator displays CA
•
A warning tone sounds at one-second intervals
The alerts continue until the clutch cools, the throttle
is released, or the clutch is fully engaged.
System Problem
In the event of a problem, do the following steps.
1. Note the driving conditions at the time the prob-
lem occurred.
2.
Record the status of the transmission at the time
of the problem (AUTO or MAN mode, gear set-
ting R, N, D, or L, current gear, engine speed,
etc.)
3. Reset the system, using the procedure below.
Reset Procedure
Transmission operation can sometimes be restored
by doing the following reset procedure:
1. Stop the vehicle when it is safe to do so. Set the
parking brake.
2. Place the selector switch in neutral and turn off
the ignition.
3.
Check all harness connectors as described in
Chapter 21.
4. Wait at least two minutes with the engine shut
down.
5. Restart the engine.
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