To facilitate testing and allow pump operation independent of the air flow meter or ECU control, all engines utilize a fuel pump test connector.
There are two basic types of fuel pump test circuits. Most late model TCCS engines use an Fp test terminal located in the check connector. With the ignition switch on, jumpering +B to the Fp terminal sends current-directly to the fuel pump.
Earlier engines use a jumper connector referred to as a 2P fuel pump check connector. This connector, when jumpered, supplies ground for the circuit opening relay run winding, allowing it to operate independently of the air flow meter Fc contact.
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