The relays
T6
and
T7
in
the engine compartment unit B1 manage the switching on of the fan
N11
at two speeds: their coils are supplied by the ignition-controlled
line (15/54), while the power lines are protected by the fuses F6
and F7, of the engine compartment unit
B1
.
Both are energized by a control signal -
earth - coming from the engine control unit
M10
.
If the engine coolant reaches a first temperature
level, the control unit
M10 sends a signal from pin 20 of connector
A to the fan 1 speed relay T6 which sends a supply to the fan N11
via the additional resistance O10 which rotates at the first speed
(slow).
If the coolant reaches a higher temperature
level, the control unit
M10 sends a signal - from pin 19 of connector
A - to the fan 2nd speed relay T7, which sends the supply directly to
the fan N11: the fan then turns at the maximum speed.