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Relays

Relays




Main relay

The main relay is located in the relay holder under the dashboard by the steering wheel.

The relay supplies the fuel pump relay, injectors, ignition discharge module, idle speed control valve, EVAP canister purge valve and EVAP canister close valve. The main relay is controlled from control module pin 31, which is grounded to operate the relay.

If the ignition has been turned off for longer than 15 minutes, the main relay will operate for 6 seconds when the ignition key is turned to the ON position.

Diagnosis


• There is no diagnosis for the electric circuit to the relay.



The main relay will then operate as soon as the control module receives impulses from the crankshaft position sensor.



The main relay will remain active for about 6 seconds after the engine has been turned off in order to supply the ignition discharge module for spark plug burn-off.

Fuel pump relay

The fuel pump relay is located in the relay holder under the dashboard by the steering wheel. This relay supplies the fuel pump.

The fuel pump relay is controlled from control module pin 56, which is grounded to operate the relay.



If the ignition has been turned off for longer than 15 minutes, the fuel pump relay will operate for 2 seconds when the ignition key is turned to the ON position. This is to build up pressure for pre-injection when the crankshaft starts to rotate.

The fuel pump relay then operates as soon as the control module receives impulses from the crankshaft position sensor

Diagnosis


• There is no diagnosis for the electric circuit to the relay. When the pump relay is activated with Tech 2, it will click but the pump will not run because the relay pin 30 is not supplied when the main relay is inactive. The main relay circuit can be supplied from fuse 16b.