Test NS-7A - Checking Fuel Pump

NOTE: For connector terminal identification, see CONNECTOR IDENTIFICATION . For appropriate wiring diagram, see WIRING DIAGRAMS at end of article.

Stop fuel system actuation test. Using DRB-II, actuate Auto Shutdown (ASD) relay. Touch fuel pump relay. See Figure . Check if fuel pump relay pulsates. If fuel pump does not pulsate, go to TEST NS-7B.
If fuel pump relay pulsates, turn ignition switch to OFF position. Disconnect fuel pump relay connector. Turn ignition switch to ON position. Put DRB-II in voltmeter mode. Probe fuel pump relay connector terminal "B" (Red wire).
If voltage is less than 10 volts, repair Red wire for an open to splice. Perform VERIFICATION PROCEDURE VER-1. If voltage is more than 10 volts, reconnect fuel pump relay connector. Disconnect fuel pump connector. See Figure .
Using DRB-II, actuate fuel system. Put DRB-II in voltmeter mode. Probe fuel pump connector terminal No. 1 (Dark Green/Black wire). If voltage is more than 10 volts, go to step 7).
If voltage is less than 10 volts, turn ignition switch to OFF position. Disconnect fuel pump relay. Using an external ohmmeter, check Dark Green/Black wire between fuel pump connector terminal No. 1 and fuel pump relay connector terminal "D".
If resistance is less than 10 ohms, replace fuel pump relay. Perform VERIFICATION PROCEDURE VER-1. If resistance is more than 10 ohms, repair open in Dark Green/Black wire. Perform VERIFICATION PROCEDURE VER-1.
If voltage was more than 10 volts in step 4), deactivate fuel system. Put DRB-II in ohmmeter mode. Probe terminal No. 4 (Black wire) of fuel pump connector.
If resistance is more than 5 ohms, repair Black wire for an open to ground. Perform VERIFICATION PROCEDURE VER-1. If resistance is less than 5 ohms, replace fuel pump. Perform VERIFICATION PROCEDURE VER-1.