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Fuel Pump Circuit Troubleshooting

If you suspect a problem with the fuel pump, check that the fuel pump actually runs; when it is on, you will hear some noise if you listen to the fuel fill port with the fuel fill cap removed. The fuel pump should run for 2 seconds when the ignition switch is turned on. If the fuel pump does not make noise, check as follows:
  1. Turn the ignition switch to LOCK (0).
  1. Open the fuse lid (A), then remove PGM-FI main relay 2 (B) from the under-dash fuse/relay box.
  1. Turn the ignition switch to ON (II).

  1. Measure the voltage between PGM-FI main relay 2 4P connector terminal No. 4 and body ground.
Is there battery voltage?
YES -
Go to Step 5 .
NO -

  1. Measure the voltage between PGM-FI main relay 2 4P connector terminal No. 2 and body ground.
Is there battery voltage?
YES -
Go to Step 6
NO -
  1. Turn the ignition switch to LOCK (0).

  1. Connect PGM-FI main relay 2 4P connector terminal No. 3 to body ground with a jumper wire.
  1. Jump the SCS line with the HDS.
  1. Disconnect ECM/PCM connector A (49P).

  1. Check for continuity between body ground and ECM/PCM connector terminal A16.
Is there continuity?
YES -
Go to Step 11 .
NO -
Repair open in the wire between PGM-FI main relay 2 and the ECM/PCM (A16).■
  1. Reinstall PGM-FI main relay 2.

  1. Connect ECM/PCM connector terminal A7 to body ground with a jumper wire.
  1. Turn the ignition switch to ON (II).

  1. Measure the voltage between ECM/PCM connector terminal A16 and body ground.
Is there battery voltage?
YES -
Go to Step 15 .
NO -
  1. Turn the ignition switch to LOCK (0).
  1. Reconnect ECM/PCM connector A (49P).

  1. Turn the ignition switch to ON (II), and measure the voltage between under-dash fuse/relay box connector B (36P) terminal No. 31 and body ground within 2 seconds.
Is there battery voltage?
YES -
NO -
Go to Step 18 .

  1. Turn the ignition switch to ON (II), and measure the voltage between under-dash fuse/relay box connector B (36P) terminal No. 31 and body ground after 2 seconds.
Is there battery voltage?
YES -
Go to Step 19 .
NO -
  1. Turn the ignition switch to LOCK (0).

  1. Turn the ignition switch to ON (II), and measure the voltage between fuel tank unit 4P connector terminal No. 2 and body ground within 2 seconds.
Is there battery voltage?
YES -
Go to Step 27 .
NO -
Go to Step 23 .
  1. Turn the ignition switch to LOCK (0).
  1. Remove PGM-FI main relay 2.

  1. Connect PGM-FI main relay 2 4P connector terminals No. 1 and No. 2 with a jumper wire.

  1. Turn the ignition switch to ON (II), and measure the voltage between fuel tank unit 4P connector terminal No. 2 and body ground.
Is there battery voltage?
YES -
Replace PGM-FI main relay 2 .■
NO -
Repair open in the wire between PGM-FI main relay 2 and the fuel tank unit 4P connector.■
  1. Turn the ignition switch to LOCK (0).

  1. Check for continuity between fuel tank unit 4P connector terminal No. 4 and body ground.
Is there continuity?
YES -
NO -