Fuel Pump and Its Circuit Check

Fuel Pump and Its Circuit Check

Circuit Diagram

Refer to Fuel Pump Control System Circuit Diagram Fuel Pump Control System Circuit Diagram.

Troubleshooting

NOTE:

The connectors of the ECM are watertight. If tester probes are directly connected to any of the connectors when checking the ECM and its circuits, the watertight performance of the connector will be affected, possibly resulting in corrosion of connector terminals and damage to electrical circuits.

Always use the special tool when checking the circuits. Connect tester probes only to the special tool's connectors.

1. Fuel pump control system check for operation

Remove fuel filler cap.
Push engine switch to change ignition mode of keyless push start system to "ON".
Confirm that fuel pump operating sound in heard from fuel filler for about 2 seconds and then it stops.

Is it in good condition?
YES -
Fuel pump circuit is in good condition. Reinstall fuel filler cap.
NO -
Go to Step 2.

2. Fuel pump relay power supply check

Reinstall fuel filler cap.
Confirm that ignition mode of keyless push start system is in "OFF".
Remove fuel pump relay from main fuse box.
Check for proper connection to fuel pump relay at each terminal.
If OK, push engine switch to change ignition mode to "ON".
Check that voltage between each fuel pump relay power supply circuit (A1, A2) and ground is battery voltage. Fuel Pump Control System Circuit Diagram

Are they in good condition?
YES -
Go to Step 3.
NO -
Repair fuel pump relay power supply circuit.

3. Fuel pump relay check

Check fuel pump relay. Testing and Inspection

Is relay in good condition?
YES -
Go to Step 4.
NO -
Replace fuel pump relay.

4. Fuel pump relay drive circuit check

Confirm that ignition mode of keyless push start system is in "OFF".
Disconnect connectors from ECM.
Check for proper terminal connection to ECM connectors.
Check the following points. Fuel Pump Control System Circuit Diagram
- Resistance of fuel pump relay drive circuit (B1): less than 3 ohms
- Resistance between fuel pump relay drive circuit and ground: infinity
- Voltage of fuel pump relay drive circuit: 0 - 1 V (with the ignition mode of keyless push start system in "ON")

Are they in good condition?
YES -
Go to Step 5.
NO -
Repair fuel pump relay drive circuit.

5. Fuel pump relay drive signal check

Confirm that ignition mode of keyless push start system is in "OFF".
Connect connectors to ECM.
Check that voltage between fuel pump relay drive circuit (B1) and ground is 0 - 1 V for 2 sec. after the ignition mode of keyless push start system in "ON". Fuel Pump Control System Circuit Diagram

Is it in good condition?
YES -
Go to Step 6.
NO -
Replace ECM and recheck DTC. Service and Repair

6. Fuel pump power supply circuit check

Confirm that ignition mode of keyless push start system is in "OFF".
Remove fuel tank.
Disconnect connector from fuel pump.
Check that resistance between fuel pump power supply circuit (B2) and ground is infinity. Fuel Pump Control System Circuit Diagram

Is it in good condition?
YES -
Go to Step 7.
NO -
Repair fuel pump power supply circuit.

7. Fuel pump power supply circuit check

Connect service wire between fuel pump circuit (B1) and ground. Fuel Pump Control System Circuit Diagram
Push engine switch to change ignition mode to "ON".
Check that voltage between fuel pump power supply circuit (B2) and ground is battery voltage.

Is it in good condition?
YES -
Go to Step 8.
NO -
Repair fuel pump power supply circuit.

8. Fuel pump ground circuit check

Confirm that ignition mode of keyless push start system is in "OFF".
Check that resistance between fuel pump ground circuit (B3) and ground is less than 3 ohms. Fuel Pump Control System Circuit Diagram

Is it in good condition?
YES -
Replace fuel pump. Fuel Pump Assembly Removal and Installation
NO -
Repair fuel pump ground circuit.