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Principle of operation, relays

Principle of operation, relays



Main relay

When the ignition switch is turned to the Drive position, power is applied to pin 27 of the control module. The control module then grounds pin 36 and the main relay operates. Simultaneously, supply voltage is applied to pin 37 of the control module from pin 87 of the main relay.

Note

Counting from the moment the ignition is switched off, the relay remains in the operated state for an additional five seconds or so, provided that the starter motor has been used.


Fuel pump relay

As soon as pulses from the crankshaft sensor are received on pins 48 and 49 of the control module, pin 3 is grounded and the pump relay operates.