Chery A21 2005, Service Manual, Page: 351 / 475

CHERY
·
A21 SERVICE MANUAL ENGINE EFI SYSTEM
28
requirement of the engine working conditions
according to the impulse signal frequency and width
of impulse.
3.14 FAN CONTROL
ECU control the fan according to water
temperature of the engine and the requirement
signal and control the fan system delay at the fit
conditions.
1) Conditions for fan running at low speed:
a) Engine coolant temperature between 96 to
℃
102 .
℃
b) There is air conditioner requirement and the
air conditioning compressor begins to work.
2) Conditions for fan running at high speed:
a) Engine coolant temperature sensor broken
b) Engine coolant temperature higher than
102 .
℃
3) Conditions of fan continue to work after the
engine stops working
A) Engine air intake temperature sensor is
broken and delay 60 seconds.
B) Engine coolant temperature sensor is broken
and delay 60 seconds.
C) Engine coolant temperature higher than
100.5
℃
, high speed delay 60 seconds.
D) Temperature of intake air more than 70.5
℃
,
delay 60 seconds.
4) Malfunction diagnose
Short circuits from high relay line to power
supply
Short circuits from high-speed relay line to
ground
Open circuits of high-speed relay line
Short circuits from low-speed relay to power
supply
Chart 3-26 Fan control schematic
Power Supply
High-Speed Relay Of Fan
Low-Speed Relay Of Fan
Double-Speed Fan
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