freightliner M2 Plus 2023 Manual page 171

08/11/2022
1. Icon Showing Descent Control Mode Engaged
Fig. 14.6, Descent Control Mode Active
08/08/2022
Fig. 14.7, New Descent Control Mode Set Speed
Pop-Up
When the vehicle's descent is complete, return the
engine brake stalk to the OFF/Auto position. At this
point the Descent Control set speed will become the
new cruise speed.
Hill Descent Upshift Feature
NOTE: It is critical that the driver maintains
complete control over the vehicle at all times.
The proper speed, and gear if in manual mode,
should be selected before the crest of any hill to
ensure a safe descent. The driver should apply
engine and service brakes appropriately during
any descent.
Automated and Automatic Transmissions
1
f611817
f611818
The Detroit ™ Automated Transmission (DT12) is
capable of upshifting automatically when descending
grades. When the vehicle is descending without
engine or service brake application, the DT12 will
upshift at 2000 rpm. If the engine or service brake is
applied during descent, the DT12 will upshift at 2400
rpm.
Transmission Low Air Warning
CAUTION
If the yellow "Caution: Transmission Air Supply
Low" popup appears while the vehicle is in
operation, slow down, safely pull the vehicle off
the road, then correct the problem.
Pneumatic controls are used to shift the
transmission. If there is inadequate air pressure, a
yellow caution pop-up will appear and the quality of
gear shifts may be degraded. See
air pressure to build before operating the vehicle.
08/11/2022
Fig. 14.8, Low Transmission Air Pressure Pop-up
CAUTION
If the red "Warning: Transmission Will Not Shift"
popup appears while the vehicle is in operation,
choose the safest location available to pull the
vehicle off the road. Prepare for the vehicle to be
immobile if the problem cannot be resolved.
If a severe loss of air pressure occurs, a red warning
pop-up will appear and the transmission will not shift.
See Fig. 14.9.
Clutch Abuse Alerts and Protections
Fig. 14.8. Wait for
f611801
14.6