Operation

Operation

K and T series only Power is supplied from fusible link D in the engine compartment fuse box on a P wire to the MEMS relay module. This feed energises the main relay which allows current to flow to the air conditioning relay module on a pair of N/K wires.

L series only Power is supplied to the main relay on a P/K wire from fuse H of the engine compartment fuse box. The energised relay then provides a feed to the air conditioning relay module on a pair of N/O wires.

K, T and L series only The current supplied to the air conditioning relay module is fed to the coils of both cooling fan relays, the condenser fan relay, and the compressor clutch relay. To energise these relays an earth path is supplied. The condenser fan relay and cooling fan relay number 1 take an earth path via a U/Y wire (U/W on vehicles fitted with a Bosch ECM) to the trinary switch.

If the engine coolant temperature is less than 116° the trinary switch will be provided an earth path via the thermo switch on a Y/W wire. The thermo switch is connected to the air conditioning switch pack by a U/R wire, which provides an earth path via the blower switch on a G wire. With an earth now supplied to the trinary switch, it in turn can provide an earth for the condenser fan relay and cooling fan relay number 1.

The compressor clutch relay takes an earth path on a U/B wire, which is controlled by the ECM.

The earth path for cooling fan relay number 2, on a S/U wire is also controlled by the ECM.