Belarus 921.6 Operator's Manual page 31

The glow plugs will not be activated, if the engine temperature is above plus 5
Meanwhile the GP indicator light 3 (Figure 2.7.1) will temporary light up for two seconds or
will not light up at all.
GP are automatically activated at the engine temperature below plus 5
starter and instruments switch is moved from the position 0 (OFF) into the position I (Instru-
ments ON). At that the GP indicator light 3 will light up on the instruments panel of the indica-
tor light unit. Duration of the GP operation depends on the engine temperature according to
Table 2.7.1. Start the engine after the light 3 goes off after the time period stated in Table
2.7.1. When the engine is started, the glow plugs remain on for some time and then go off.
Duration of the GP operation after the engine start depends on the engine temperature at the
moment when the GP are activated (see Table 2.7.1).
GP will be deactivated, if the engine was not started within (10±1) s after the light 3
goes off.
The glow-plugs operation algorithm includes following emergency modes:
- when the starter and instruments switch key is moved from position 0 (OFF) into
position I (Instruments are ON), the GP indicator light 3 starts blinking continuously at the
frequency ≈ 2 Hz. This means, that there is malfunction in the GP operation system – all
glow plugs are short-circuited or their connection is discontinued (disconnected from the
GP control unit), no power supply for the GP control unit or power supply wire is damaged.
Meanwhile the GP control unit stops power supply to the glow plugs in case of short-
circuit;
- when the engine is started, the GP indicator light 3 will start blinking for one minute
with three seconds cycle duration and blinking duration of 0.25 second. Quantity of blinks
can might vary. The starting process is performed normally. This means, that one or more
(but not all of them) plugs are faulty. Quantity of blinks during one cycle equals to the
quantity of non-operating GP;
If malfunctions stated above are not remedied, the engine start at lower tempera-
tures might become difficult.
- during the starting preheating and prior the engine start the indicator light 3 blinks at
the frequency ≈ 1 Hz. This is the evidence of the GP temperature sensor short-circuit or the GP
temperature sensor circuit discontinuation (if the controller with external sensor is installed) or
this sensor is faulty. In such case, the duration of the engine starting preheating and the GP
warming after the engine start shall be established as at the engine temperature of minus 20
°С according to Table 2.7.1. The plugs activation delay shall be three seconds after the starter
and instruments switch key is moved from the position 0 (OFF) into position I (Instruments are
ON).
IT IS PROHIBITED TO OPERATE THE TRACTOR PRIOR TO THE GLOW PLUGS
SYSTEM TROUBLESHOOTING, SINCE IT CAN LEAD TO THE ACCUMULATOR BAT-
TERIES DISCHARGE!
Table 2.7.1 – The GP operation duration depending on the engine temperature
The engine
temperature, °С
Above plus 5
From plus 5 to 0
From 0 to minus 10
From minus 10 to minus
15
From minus 15 to minus
20
From minus 20 to minus
25
Below minus 25
Duration of the engine start-
ing preheating, s.
0
15
20
25
35
42
50
31
921.6-0000010 OM
0
С when the
Warming duration after
the engine start, s.
0
25
50
75
100
125
150
0
С.