Help! no power to the fuel pump

[mrnorm1984]

no power to the fuel pump. I changed the pump relay. still no power. when I hook a jumper wire fom the battery to the g terminal on the alcl diagnostic connector I get power that way. right now I have a jumper wire straight to the pump and running it that way for now. anyone have any ideas of this problem. it's 1984 coupe thanx mrnorm. the fuses good

 

[ecss]

no power to the fuel pump. I changed the pump relay. still no power. when I hook a jumper wire fom the battery to the g terminal on the alcl diagnostic connector I get power that way. right now I have a jumper wire straight to the pump and running it that way for now. anyone have any ideas of this problem. it's 1984 coupe thanx mrnorm. the fuses good

There are three ways to energize the fuel pump.

1) 12 volts to pin G. The 12 volts passes through the normally closed relay contacts to the fuel pump.

2) When there is 4 psi or more oil pressure the oil pressure switch closes and 12 volts from a Orange wire provides 12 volts to the fuel pump.

3) The ECM applies 12 volts on a Dark Green/White wire when you turn the ignition On. This energizes the fuel pump relay. The fuel pump will run for 2 seconds and shut off if no ignition reference pulses are seen by the ECM. The ECM will continue to enable the fuel pump relay if it sees reference pulses (engine cranking).

First verify the insulation of the wires at the relay socket are not shorting out.
Remove the relay from the socket.

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Use a volt meter to measure the voltage on the Dark Green/White wire.
Use the Black/White wire at the relay for your ground probe.

Do not use a test light which could damage the ECM.
Verify what the voltage is when cranking the engine. Should be 12 volts.
If no 12 volts the ECM is probably bad.

Use a volt meter and measure the voltage on Pin E the Orange wire. Should be 12 volts. If no 12 volts a fusible link is probably blown.