SECTION 05: COOLING SYSTEM
18
DOB 2490-2789 | X3-45 Commuter PA1605 Maintenance Manual (Final Version – Rev.2 April 2016)
The settings are:
Engine
coolant
temp.
Air intake
temp.
Allison
trans. oil
temp.
temperature
rising
208°F: fan
engages in
HIGH
SPEED
194°F: fan
engages in
HIGH
SPEED
230°F: fan
engages
in HIGH
SPEED
203°F: fan
engages in
LOW
SPEED
176°F: fan
engages in
LOW SPEED
216°F: fan
engages
in LOW
SPEED
temperature
dropping
203°F: fan
HIGH
SPEED
disengages
189°F: fan
HIGH
SPEED
disengages
225°F: fan
HIGH
SPEED
disengage
s
198°F: fan
LOW
SPEED
disengages
170°F: fan
LOW SPEED
disengages
210°F: fan
LOW
SPEED
disengage
s
WARNING
DO NOT work near the fan with the engine
running or the ignition switch in the ON
position. The engine fan can engage at any
time without warning. Anyone near the fan
when it turns on could be seriously injured.
13.1 LOCKING FAN CLUTCH FOR
EMERGENCY OPERATION
13.1.1 Electrical Locking
If the cooling fan clutch does not function due to
an electrical control system malfunction and the
engine is overheating, active the fan clutch
execute the following procedure:
1. Turn the ignition switch to the ON position.
2. Activate the dashboard Telltale Light Test
switch 3 times within 4 seconds.
3. In the engine compartment, set the starter
selector switch to REAR START and then
start the engine from the rear.
WARNING
Potential Accident Risk. Always use extreme
caution when working in the vicinity of hot,
rotating or moving parts.
While in this mode, the rear start push-button
can be used to manually engage the fan clutch.
The multiplex system knows when the engine is
already running, and it will not activate the
starter.
4. Press the push-button one time to engage
the clutch to 1
st
speed, press a second time
to engage to 2
nd
speed, press a third time to
stop the fan, press once again to return to 1
st
speed.
You can activate the fan clutch through a Driver
Information Display menu also. For more detail,
refer to “Forced Activation of the Radiator Fan
Clutch” paragraph in Section 06: ELECTRICAL.
NOTE
If the fan clutch does not engage using this
procedure then the clutch is faulty or the wiring
between the multiplex module and the clutch
is faulty. Mechanically lock the fan as
described hereafter in section 13.1.2.
13.1.2 Mechanical Locking
Once mechanically locked, the fan is rigidly
connected to the drive mechanism and will
rotate continuously, with no considerations for
the cooling needs. This is an emergency
situation and the vehicle shall not be operated in
that situation for an extended period.
In case of a magnetic clutch malfunction:
1. Turn the ignition switch to the OFF position
and set starter selector switch to the OFF
position to prevent accidental starting of the
engine.
2.
Disconnect the fan clutch electrical
connector.
3. Unscrew and remove the 4 spare M6x12 hex
bolts screwed to the angle on the fan
gearbox mounting support (see figure 30).
4. Screw in 4 hex bolts through the clutch
anchor plate into the rotor. Using the
automatic belt tensioner, release tension on
the drive belt in order to be able to rotate the
fan clutch drive mechanism by hand.
Tightening torque: 7.5 lbf-ft.
