Fuel Pump Relay

Fuel Pump Relay
The control unit can only monitor activation of the relay but not of the pump itself. A safety circuit ensures the relay can only be activated with the engine running and only shortly after switching the ignition lock to position 2 in order to build up pressure.

Once the engine shuts down, the DME control unit no longer recognized engine speed and immediately switches off the relay. This ensures that the fuel pump cannot continue running when the engine turned off.