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. Remove PGM-FI main relay 2 (A) in the driver's 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 14 .
NO -
Go to Step 6 .
  1. Turn the ignition switch to LOCK (0).
  1. Remove PGM-FI main relay 1 (A) and ETCS control relay (B) in the under-hood fuse relay box.
  1. Jump the SCS line with the HDS.
  1. Disconnect ECM/PCM connector A (44P).
  1. Disconnect the engine wire harness 23P connector at left side of engine compartment.
  1. Disconnect the driver's under-dash fuse/relay box connector F (33P).
  1. Connect PGM-FI main relay 1 4P connector terminal No. 2 to body ground with a jumper wire.
  1. Check for continuity between driver's under-dash fuse/relay box connector F (33P) terminal No. 31 to body ground.
Is there continuity?
YES -
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 20 .
NO -
Except KN model: Go to Step 15 .
KN model:
  1. Turn the ignition switch to LOCK (0).
  1. Disconnect inertia switch 3P connector.
  1. Connect inertia switch 3P connector terminals No. 1 and No. 3 with a jumper wire.
  1. Turn the ignition switch to ON (II).
  1. Measure the voltage between PGM-FI main relay 2 4P connector terminal No. 2 and body ground.
Is there battery voltage?
YES -
NO -
  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 (44P).
  1. Check for continuity between body ground and ECM/PCM connector terminal A15.
Is there continuity?
YES -
Go to Step 24 .
NO -
Repair open in the wire between PGM-FI main relay 2 and the ECM/PCM (A15).■
  1. Reinstall PGM-FI main relay 2.
  1. Connect ECM/PCM connector terminal A6 to body ground with a jumper wire.
  1. Turn the ignition switch to ON (II).
  1. Measure the voltage between ECM/PCM connector terminal A15 and body ground.
Is there battery voltage?
YES -
Go to Step 28 .
NO -
Replace PGM-FI main relay 2 .■
  1. Turn the ignition switch to LOCK (0).
  1. Reconnect all connectors.
  1. Turn the ignition switch to ON (II), and measure the voltage between driver's under-dash fuse/relay box connector F (33P) terminal No. 22 and body ground within 2 seconds.
Is there battery voltage?
YES -
NO -
Go to Step 31 .
  1. Turn the ignition switch to ON (II), and measure the voltage between driver's under-dash fuse/relay box connector F (33P) terminal No. 22 and body ground after 2 seconds.
Is there battery voltage?
YES -
Go to Step 32 .
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 40 .
NO -
Go to Step 36 .
  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 -
  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 -