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Fuel Pump and Its Circuit Check: Troubleshooting

WARNING: This page is about a different variant/trim than selected.

NOTE:

Before troubleshooting, be sure to read the Precautions of ECM Circuit Inspection:N32A .
When measuring circuit voltage and/or pulse signal at ECM connector, connect special tool to ECM and/or the ECM connectors.

TROUBLESHOOTING CHART

Step	Action	YES	NO
1	Fuel pump control system check for operation Turn ignition switch to ON position, confirm fuel pump operating sound from near fuel pump. It should sound for about 2 seconds and stop. Is it in good condition?	Fuel pump circuit is in good condition.	Go to Step 2.
2	Fuel pump relay power supply check Remove fuel pump relay from fuse box with ignition switch turned off. Check for proper connection to fuel pump relay at each terminal. If OK, turn ignition switch to ON position check that voltage between each fuel pump relay power supply circuit (A1 - A2) and vehicle body ground is battery voltage. Is it in good condition?	Go to Step 3.	Repair or replace defective wire harness.
3	Fuel pump relay check Check fuel pump relay, see Fuel Pump Relay Inspection . Is relay in good condition?	Go to Step 4.	Replace fuel pump relay.
4	Fuel pump relay drive circuit check Disconnect connector from ECM with ignition switch turned off. Check that fuel pump relay drive circuit (A3) is as follows. Wiring harness resistance of fuel pump relay drive circuit is less than 3 Ω. Insulation resistance between fuel pump relay drive circuit and vehicle body ground is infinity. Circuit voltage of fuel pump relay drive circuit is 0 - 1 V with ignition switch ON. Are they in good condition?	Go to Step 5.	Repair or replace defective wire harness.
5	Fuel pump relay drive signal check Connect connector to ECM with ignition switch turned off. Install fuel pump relay to fuse box. Check that voltage between fuel pump relay drive circuit (A3) and vehicle body ground is 0 - 1 V within 2 sec. after turning ignition switch to ON position. Is it in good condition?	Go to Step 6.	Substitute a known-good ECM and recheck.
6	Fuel pump power supply circuit check Turn off ignition switch. Detach fuel tank, see Fuel Tank Removal and Installation . Disconnect connector from fuel pump. Check that resistance between fuel pump power supply circuit (A4) and vehicle body ground is infinity. Is resistance infinity?	Go to Step 7.	Repair or replace fuel pump power supply circuit.
7	Fuel pump power supply circuit check With ignition switch in ON position, check that voltage between fuel pump power supply circuit (A4) and vehicle body ground is battery voltage. Is it in good condition?	Go to Step 8.	Repair or replace defective wire harness.
8	Fuel pump ground circuit check Turn off ignition switch. Check that resistance between fuel pump ground circuit (A5) and vehicle body ground is less than 3 Ω. Is it in good condition?	Faulty fuel pump.	Repair or replace defective wire harness.