Fuel Injector Circuit Check

Fuel Injector Circuit Check

Circuit Diagram

Refer to Fuel Injector Control System Circuit Diagram Fuel Injector 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 injector check for operating sound

Using sound scope, check each injector for operating sound with engine cranking.

Do all injectors make operating sound?
YES -
Fuel injector circuit is in good condition.
NO -
Go to Step 2.

2. Fuel injector resistance check

Confirm that ignition mode of keyless push start system is in "OFF".
Disconnect connectors from fuel injectors.
Check for proper connection to fuel injector at each terminals.
If OK, check all fuel injectors for resistance. Fuel Injector On-Vehicle Inspection

Are all injectors at specified resistance?
YES -
Go to Step 3.
NO -
Replace fuel injector. Fuel Injector Removal and Installation

3. Fuel injector insulation resistance check

Check that resistance between each fuel injector terminal and ground is infinity.

Are they in good condition?
YES -
Go to Step 4.
NO -
Replace fuel injector. Fuel Injector Removal and Installation

4. Fuel injector power supply circuit check

Push engine switch to change ignition mode to "ON".
Check that voltage between each fuel injector power supply circuit (B1, B2, B3, B4) and ground is battery voltage. Fuel Injector Control System Circuit Diagram

Is it in good condition?
YES -
Go to Step 5.
NO -
Repair fuel injector power supply circuit.
If it is in good condition, go to Component Tests and General Diagnostics ECM Power and Ground Circuit Check.

5. Fuel injector drive circuit check

Confirm that ignition mode of keyless push start system is in "OFF".
Disconnect connectors from ECM.
Check the following points. Fuel Injector Control System Circuit Diagram
- Resistance of each fuel injector drive circuit (A1, A2, A3, A4): less than 3 ohms
- Resistance between each fuel injector drive circuit and ground: infinity
- Voltage of each fuel injector 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 6.
NO -
Repair fuel injector drive circuit.

6. Fuel injector check

Check fuel injector. Fuel Injector Inspection

Is it in good condition?
YES -
Replace ECM and recheck DTC. Service and Repair
NO -
Replace fuel injector. Fuel Injector Removal and Installation