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UNDERSTANDING YOUR INSTRUMENT PANEL 129
4
Settings with the A uxiliary Heater switched on
(only with Water Heater)In preheat mode, the blower is automatically switched
on at blower speed 1 when the water heater is switched
on. When driving, the airflow control switch (2) can be
set as desired.NOTE: Only on vehicles with automatic heater
control/regulated air conditioner:
Before switching on the heater or entering the switch-
on time, the temperature control (1) must be set to
maximum heater output (as illustrated).
Set the air distribution control (3) as required between
Y and Z.
AUXILIARY HEAT EXCHANGER IN LOAD
COM PA RTM ENT, ONLY WI TH A UXILIA RY WA TER
HEATER (OPTIONAL)
The auxiliary heat exchanger switch
is located on the right next to the
steering column.
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130 UNDERSTANDING YOUR INSTRUMENT PANELTo switch on at blower speed 1:
Press the upper section, the left-hand indicator lamp in
the switch lights up.
To switch on at blower speed 2:
Press the lower section, the right-hand indicator lamp
in the switch lights up.
To switch off :
Press the switch to the middle position.
Operation is only possible when the key is turned to
position 2 in the ignition lock.
NOTE: The auxiliary heat exchanger in the load
compartment should be switched off at coolant
temperatures below 176 °F (+80 °C) to quickly de-fog
and de-ice the windshield and front side windows.
A UXILIA RY HEA TER – TIPS FOR COPING WITH
PROBLEMSThe heater either does not switch on or automatically
switches off:
Insufficient fuel, fill up the fuel tank. Start up heater
several times, until the fuel lines are filled.
The auxiliary heater will automatically switch off if
the fuel level is under about 4 US gal (15 l).
The fuses in the fuse box are damaged. Electric
fuses.
The battery voltage is too low, an undervoltage
protector switches off the heater if the battery
voltage falls below about 10 volts.
The heater motor does not run
The battery voltage is too low, check the battery.
Batteries.
The fuses in the fuse box are damaged.
Electric fuses.
The heater motor is damaged.
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UNDERSTANDING YOUR INSTRUMENT PANEL 131
4
Overheating (Water Heater) Insufficient coolant, check coolant level.
The heater will remain switched off after it has been
overheated a number of times (about 10 times in
succession). Have the fault repaired by an
authorized Sprinter Dealer.
Overheating (A ir Heater) The air channels are clogged.
The heater can be restarted once the fault has been
repaired. When this is done, the heater should be
switched on and off.
The heater will remain switched off after it has been
overheated a number of times (about 3 times in
succession). Have the fault repaired by an
authorized Sprinter Dealer.
NOTE: Repairs should only be made by an authorized
Sprinter Dealer.
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Freightliner-all.book Pag e 132 Monday, December 1, 2003 2:54 PM
Page 133 of 272