The power supply to fan
N11
is controlled
by two relays
R7
(1. speed) and
R6
(2. speed), located
in relay control unit
B3
.
Both relays are supplied with power directly
from the battery - junction unit
A5
- by a line protected
by a special fuse
F9
for
R7
and
F8
for
R6
,
all located in
B3
.
Functional description
if the coolant temperature reaches the first
temperature stage, or the 4-stage pressure switch
K10
-
pin 3 - indicates to control unit
M10
- pin 34 of connector
A - that the first pressure stage has been reached, control unit
M10
sends a signal to 1st speed relay
R7
from pin 13 of connector
A.
if the engine coolant reaches a higher temperature
level, or the 4-stage pressure switch
K10
- pin 6 - indicates
to control unit
M10
- pin 35 of connector A - that a higher
pressure level has been reached, control unit
M10
sends
an earth signal to 2nd speed relay
R6
from pin 4 of connector
A.
When 1st speed relay
R7
is excited,
it sends an earth signal through additional resistance
O10
to operate fan
N11
, which turns at the first speed (slow).
When 2nd speed relay
R6
is excited,
it sends an earth signal directly to fan
N11
, which turns
at the maximum speed.