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Fuel Pump Relay Signal

  1. Pull fuel pump relay out of fuse block/relay panel. Connect voltmeter between terminals No. 46 and 47 of relay panel sockets. See Fig 1. Briefly actuate starter. Voltmeter should indicate close to 9.5 volts.
  2. If reading is correct, check fuel pump relay and fuel pump. If reading is incorrect, connect voltmeter between terminal No. 46 of relay panel socket and ground. Turn ignition on. Voltmeter should indicate close to 12 volts.
  3. If reading is incorrect, check for open circuit in wiring. If reading is correct, check wiring between ignition control unit and fuse block/relay panel as follows.
  4. Remove control unit panel located on passenger side footwell. Unplug ignition control unit connector. Using an ohmmeter, check continuity between terminal No. 21 of control unit connector and socket No. 47 of fuse block/relay panel.
  5. Ohmmeter reading should be close to zero ohms. If reading is incorrect, check for open circuit in wiring. If reading is correct, replace ignition control unit.
Fig 1: Fuel Pump Relay Signal Test
G34169