Volkswagen Passat '97, User Manual

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34
1.9-ltr. TDI Engine AFN
Radiator fan run-on
Electric circuit
30
15
X
31
30
15
X
31
S
V7
J248
J397
N39
3
A radiator fan run-on facility controlled by the
engine management system is being used in
the 1.9-ltr. 81kW TDI engine for the first time.
The advantage of this is that the radiator fan
run-on time is variable and can consequently
be adapted to the previous operating
conditions and load conditions of the engine. The run-on time is determined by the engine
control unit via a characteristic map. Allowance
is also made for the coolant temperature and
engine load during the final minutes of car
operation before the engine is turned off.
IN OUT
Components
J248 Diesel direct injection
system control unit
J397 Cooling fan run-on
relay
N39 Series resistor for
coolant fan
S Fuse
V7 Coolant fan
SSP 192/086
Radiator fan run-on relay J397 Self-diagnosis
Open circuit /short circuit to earth
Short circuit to positive
The radiator fan run-on relay J397 is designated as blower relay J323 in the self-diagno-
sis.