freightliner BUSINESS CLASS M2 Driver Manual page 118

Axle Shift Switch
The axle shift switch is a two-position guarded rocker
switch (Fig. 8.24) installed on vehicles with two-
speed axles.
10/26/2001
Fig. 8.24, Axle Shift Switch
To shift the axle from low speed to high speed, press
the upper half of the rocker momentarily (at the
LED). To turn the axle shift off (switch from high
speed back to low speed), press the upper half of
the rocker again. When the axle has shifted speed,
the LED turns off.
When the panel lights are on, the AXLE SHIFT leg-
end is backlit in green.
IMPORTANT: The axle shift rocker switch is
guarded to prevent unintentional switch activa-
tion. If the LED in the switch begins to blink dur-
ing normal operation, when the switch has not
been activated, this indicates an error condition.
Bring the vehicle to an authorized Freightliner
service facility as soon as possible.
When the axle shift switch is pressed, three re-
sponses are possible: a normal response, a slow re-
sponse, and an abnormal response.
Normal Response: The LED in the switch blinks until
the axle shifts speed. At this point, the LED comes
on steady and stays illuminated. In normal operation,
the axle may shift so quickly that the blinking of the
switch is barely noticeable.
If operation of the switch is not possible for any rea-
son (interaxle lock is on, ignition is turned off, etc.),
the LED will stop blinking and turn off.
Slow Response: If operation of the switch is slowed
for any reason (by cold weather, low air pressure,
etc.), the switch will continue to blink until the axle
shifts. As in the normal response, the LED comes on
steady and stays illuminated.
Abnormal Response: If the LED blinks for more than
30 seconds, the axle shift function/mechanism may
not be operating correctly. Bring the vehicle to an
authorized Freightliner service facility for testing.
Axle Switch Interlock
NOTE: On vehicles with tandem drive axles,
there is an interlock that prevents an axle from
shifting speed whenever the interaxle lock is on.
If the axle shift switch is pressed when the interaxle
lock is on, the axle shift will not be completed. The
LED does the following:
f610594
•
If the LED is off, the LED comes on briefly and
turns off again.
•
If the LED is on, it stays on.
To complete the axle shift, turn off the interaxle lock
and press the axle shift switch again. If still needed,
the interaxle lock can then be reactivated.
Drivetrain
8.30