Fuel Injectors 5 - 8, Checking

Fuel Injectors 5 - 8, Checking

The following test procedure is used to diagnose all fuel injectors controlled by the Engine Control Module (ECM) 2 (J624).

Special tools, testers and auxiliary items required

• Multimeter.

• Diode test lamp (12V).

• Wiring diagram.

Test requirements

• The Engine Control Module (ECM) 2 (J624) fuses OK.

• The Engine Speed (RPM) Sensor (G28) OK.

• Battery voltage at least 12.5 volts.

• All electrical consumers such as, lights and rear window defroster, switched off.

• Vehicles with automatic transmission, shift selector lever into position " P" or "N".

• A/C switched off.

• Ground (GND) connections between engine/transmission/chassis OK.

• Ignition switched off.

- Observe safety precautions.

- Observe rules for cleanliness.

Test procedure

- Perform a preliminary check to verify the customers complaint. Refer to => [ General Diagnosis ] General Diagnosis.

Start diagnosis

- Remove the intake manifold. Refer to Fuel Injection and Ignition Repair Information.

- Disconnect the Fuel Injector electrical harness connector - arrow - from the Fuel Injector to be tested.





Checking internal resistance

- Using a multimeter, check terminals 1 to 2 of the Fuel Injector to be tested for resistance.





Specified value: 1.3 to 5.0 ohms (at approx. 20° C)

If the specified value was not obtained:

- Replace the faulty Fuel Injector Fuel Injection and Ignition Repair Information.

If the specified value was obtained:

Checking activation

- Connect a diode test lamp (12V) to the Fuel Injector electrical harness connector terminals 1 and 2 of the Fuel Injector to be tested.





- Operate the starter and test the activation of the Fuel Injector.

LED should flicker.

- Switch the ignition off.

If LED flickers:

- Replace the faulty Fuel Injector Fuel Injection and Ignition Repair Information.

If LED does not flicker:

Checking activation and wiring

If the manufacturers test box is being used. Perform the following step.

- Install the test box. Refer to Fuel Injection and Ignition Repair Information.

If the manufacturers test box is not being used. Perform the following step.

- Remove the Engine Control Module (ECM) 2 (J624 ). Refer to => [ Engine Control Module 1, Removing and Installing ] Engine Control Module 1, Removing and Installing.

- Using a Multimeter, check the electrical harness connector terminals of the Fuel Injector to be tested to the Engine Control Module (ECM) 2 (J624) electrical harness connector T60a terminals for an open circuit.





Specified value: 1.5 ohms Max.

If the specification is not obtained:

- Check the wiring for a short circuit to each other, Battery (+), Ground (GND), or an open circuit.

- Check the electrical harness connector for damage, corrosion, lose or broken terminals.

- If necessary, repair the faulty wiring connection.

If no malfunction is detected in the wiring:

- Replace the Engine Control Module (ECM) 2 (J624 ). Refer to => [ Engine Control Module 1, Removing and Installing ] Engine Control Module 1, Removing and Installing.

- Install the intake manifold. Refer to Fuel Injection and Ignition Repair Information.

Final procedures

After repair work, the following work steps must be performed in the following sequence:

1. Check the DTC memory. Refer to => [ Diagnostic Mode 03 - Read DTC Memory ] Diagnostic Mode 03 - Read DTC Memory.

2. If necessary, erase the DTC memory. Refer to => [ Diagnostic Mode 04 - Erase DTC Memory ] Diagnostic Mode 04 - Erase DTC Memory.

3. If the DTC memory was erased, generate readiness code. Refer to => [ Readiness Code ] Monitors, Trips, Drive Cycles and Readiness Codes.

- End of diagnosis.