KAMAZ 5490 Operation Manual page 210

The economic mode is used to keep the engine
and the driver's cab warm when the engine is idle for 8
hours maximum.
The positions of the key switch are marked with
figures 3 and 8 correspondingly.
6.1.2 Heat controller knob 4 is used to control the
cab heater fan (provided that the coolant fluid
temperature is more than 55 °С, key switch of the cab
heater on the dash is OFF, frame connection available)
the following way:
а) with the knob in the utmost left position the cab
heater fan is OFF;
б) with the knob in the utmost right position the
cab heater fan is continuously ON;
в) with the knob in the middle position the fan
will runin cycles. Cycle duration is 10min.
Example: if the knob is in a position when the
heater fan is ON for 4min, then it will be ON again only
in 6min for 4min. Thus, it will continue cycling unless
the knob is turned or the heater is switched off. After
each turn of the knob (between two extreme positions),
the cab heater fan is activated within 2 min – 8 min
interval.
6.1.3 LED 3 indicates the pre-heater status:
- LED glows - pre-heater ON;
- LED blinks – malfunction (failure). The
number of blinks and pauses corresponds to a certain
malfunction code (refer to Table 2).
- LED OFF – pre-heater OFF.
Attention!
To restart the pre-heater when it automatically
stopped, the key switch 1 shall be in position «О» and
then, not earlier than in 5-10 sec back in position «I»
Heat controller knob poses. 4 for KAMAZ
vehicles of «Euro 3» and «4» is not used (Car maker
does not connect the relay of cabin heater fan to the
harness of pre-heater on these cars).
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