Fiat 1996 Brava Service Manual page 265

Engine
Fuel system
10.
MANAGEMENT OF THE RADIATOR FAN
Bravo-Brava igi 16v
98 range
NOTE Since the coo/ant temperature is detected by the appropriate sensor there is no longer a thermal
contact on the radiator.
The engine control unit operates the engagement of the radiator fan according to the temperature of the
coolant andwhether or not there is a climate control system.
In the case of versions with climate control, there are two fan operating speeds, managed according to
different logics, entirely independent of one another.
- According to the coolant temperature.
Low speed: this is switched on when the temperature of the coolant reaches Ti = 96.5 °C;
high speed: this is switched on when the temperature of the coolant reaches T2 = 102 °C.
The fan is switched off with a temperature hysteresis of around 3 °C.
- According to the condition of the four stage pressure switch.
Low speed: this is switched on when stage II of the pressure switch is triggered;
high speed: this is switched on when stage III of the pressure switch is reached.
T
T2
T1^
1
2
3
L
f
1
^^-*v
/ l
/ 1
/ 1
T\ \ / j
/ T
/ 1
/ 1
/ l
X i
0
1 1 1
OFF
OFF
i \ J i
i
v
- ^ i
i i
o ;
i i !
I I
2
OFF
OFF
! o ^ *"
1 I |1 I
! i 2 I :
i I i
1 ;
ON
; |
ON
w
t
Ti = 96.5 X
T2 = 102 °C
ON: pressure switch activated
OFF: pressure switch deactivated
1. Fan state. 0 = off
1 = low speed
2 = high speed
2. Four stage pressure switch level II
3. Four stage pressure switch level III
4. Engine coolant temperature progress
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Print no. 506.670/76