244001989 - E6021 FUNCTIONAL DESCRIPTION OF COMPRESSOR ENGAGEMENT

Operational Description

The compressor activation circuit is controlled by relay T05, contained in engine bay junction unit B001. This is supplied directly by a line from the battery that enters at pin 1 of control unit connector F and is protected by fuse F19, located in the control unit.During engine start-up, control unit M010 of connector A pin 13 excites relay T09 to provide it with an earth signal. The relay receives power directly from the battery protected by fuse F18. Relay T05 is supplied in turn and excited by engine control unit M010, connector A pin 18, when compressor activation is required.The compressor actiation request comes from climate control unit M070 - pin 4. The signal firstly reaches electronic thermostat N086 and then antifrost thermostat K160. Engine control unit M010 processes signal from both frost thermostats and multistage pressure switch K010. If the pressure and temperature readings from the air conditioning system are correct, the control unit excites relay T05 via pin 18 of connector A to supply compressor L020.Climate control unit M070 receives a power supply via the ignition and direct from the battery. The former is protected by fuse F31 hosed in underfacia junction unit B002 and the latter is protected by fuse F34 housed in optional junction unit B101. The climate control unit contains its own internal lighting that comes on when the side lights are on.