Peterbilt Medium Duty Trucks Operator's Manual after 1-07

Operating Instructions
WARNING! Do not work on or near the fan with
the engine running. Anyone near the engine fan
when it turns on could be seriously injured. If it
is set at MANUAL, the fan will turn on any time
the ignition key switch is turned to the ON position.
In AUTO, it could engage suddenly without
warning. Before turning on the ignition or
switching from AUTO to MANUAL, be sure no
workers are near the fan.
CAUTION: The fan or equipment near it could be
damaged if the fan turns on suddenly when you
do not expect it. Keep all tools and equipment
away from the fan.
NOTE: Do not operate the engine fan in the MAN-
UAL position for extended periods of time. The fan
hub was designed for intermittent operation. Sustained
operation will shorten the fan hub's service
life as well as reduce fuel economy.
Cruise Control (Option)
Operating the Engine
This feature improves fuel mileage and reduces driver
fatigue by maintaining a constant vehicle speed. The
cruise control will only operate above a programmed minimum
vehicle speed, 15 mph for the CAT 3126B engine,
30 mph for the Cummins ISC engine.
Engaging the Cruise Control
02901
NOTE: Ensure that the vehicle speed is above the
minimum cruise control speed and the engine
speed is above 1100 rpm.
1. Move the ON/OFF switch to the ON position.
NOTE: Toggling the SET/RESUME switch to the
RESUME position at this point will select the previously
set cruise speed.
2. Accelerate the vehicle to the desired cruise speed.
Medium Duty (R10/06) Y53-6008 – 65 –