FUNCTIONAL DESCRIPTION

Relay switches T06 and T07 of the engine compartment junction unit B001 manage the switching on of the two speed fan N011: the power lines are protected by fuses F06 and F07, also in engine compartment junction unit B001.

Both are energised by an earth control signal coming from the Powertrain Control Module M010.

If the engine coolant reaches an initial temperature level, or the linear sensor K120 signals to the control unit M010 - pin 10 of connector A - that a certain pressure level has been reached, then the control unit M010 sends a signal - from pin 39 of connector A - which energises the 1st speed fan relay switch T06; this sends the power supply to the fan N011 through the additional resistor O010: the fan turns at the first speed (slow).

The linear sensor K120 receives a power supply and reference earth from the Powertrain Control Module M010, pins 1 and 3 of connector A.

If the engine coolant reaches a higher temperature level, or the linear sensor K120 signals to the control unit M010 that a higher pressure level has been reached, then the control unit M010 sends a signal - from pin 38 of connector A - which energises the 2nd speed fan relay switch T07 which sends the power supply directly to the fan N011: the fan turns at the maximum speed.

The engine temperature sensor K036 measures the engine temperature and receives a reference earth from pin 7 of connector B of control unit M010 and sends a signal proportional to the engine coolant temperature to pin 19 of connector B.