Taylor-Dunn G0-010-00, Service And Replacement Parts Manual

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9929758 R01 - 2019 TAYLOR-DUNN G-100 Service Manual
© Copyright TAYLOR-DUNN
5. Turn on the key switch to activate the pump and
check the system pressure on the gauge. If system
pressure of 58 ± 2 psi is observed, the ignition switch,
ECU, fuel pump, and pressure regulator are working
properly. Turn the key switch off and depress the
valve button on the tester to relieve the system
pressure.
Normal Fuel Pressure:
58 ± 2 psi (400 ± 14 kPa)
NOTICE
If the fuel pressure is out of specification, replace the
fuel pump assembly.
6. If the pump did not activate (Step 5), disconnect the
harness connector from the fuel pump. Connect a DC
voltmeter across terminals “3” and “4” in the plug on
the vehicle fuel pump harness. Turn on the key switch
and observe voltage to ensure a minimum of 7 volts is
present.
NOTICE
If the voltage was below 7 VDC, test the battery, ignition
switch, relay(s), wiring harness and ECU.
7. If the reading is between 7 and 14 volts, turn key
switch off and connect an ohmmeter between
terminals “3” and “4”' at the white fuel pump
connector to check for continuity within the fuel pump.
NOTICE
If there was no continuity between the pump terminals,
replace the fuel pump assembly.
8. If voltage at the plug was within the specified range,
and there was continuity across the pump terminals,
reconnect the plug to the fuel pump, making sure you
have a clean connection. Turn on the key switch and
listen for the pump to activate.
NOTICE
If the pump starts, repeat steps 3, 4 and 5 to verify
correct pressure.
9. If the pump still does not operate, check for correct
ECU operation by plugging in a known-good ECU of
the same model.
NOTICE
If the pump still does not operate, replace the fuel pump
assembly.
FUEL SYSTEM