Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Fuel Injectors --, CHECKING
Observe all safety precautions: SAFETY PRECAUTIONS
View clean working conditions: CLEAN WORKING CONDITIONS
Use only gold-plated terminals when servicing any component with gold-plated electrical harness connector terminals.
For wiring diagrams, component locations, and connector views, Refer to the applicable wiring diagram.
The following test procedure is used to diagnose all fuel injectors.
Special tools and workshop equipment required
- multimeter.
- Wiring diagram.
Test requirements
- 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 connections between engine/transmission/chassis OK.
- Switch the ignition Off.
Test procedure
-- Perform a preliminary check to verify the customers complaint. Refer to PRELIMINARY CHECK
Start diagnosis
-- Remove the engine cover.
-- Disconnect the Fuel Injectors -- electrical harness connectors from Fuel Injectors -N30, N31, N32, N33-.
-4-
Checking internal resistance
-- Using a multimeter, check the Fuel Injector -- terminals 1 to 2 for resistance.
50 K Ω - 700 K Ω (Depending on Temperature)
If the specified value was Not obtained:
-- Replace the malfunctioning Fuel Injector --.
If the specified value was obtained:
-- Remove the Engine Control Module (ECM) -J623-.
-- Using a multimeter, check the Fuel Injectors -- electrical harness connector terminals to the Engine Control Module (ECM) -J623- electrical harness connector T60 terminals for a short to ground or voltage, high resistance or an open circuit.
| Component | Fuel Injector -- electrical harness connector terminals | Engine Control Module (ECM) -J623- electrical connector T60 terminals |
|---|---|---|
| Cylinder 1 Fuel Injector -N30- | 1 | 46 |
| 2 | 31 | |
| Cylinder 2 Fuel Injector -N31- | 1 | 2 |
| 2 | 17 | |
| Cylinder 3 Fuel Injector -N32- | 1 | 1 |
| 2 | 16 | |
| Cylinder 4 Fuel Injector -N33- | 1 | 47 |
| 2 | 32 |
Specified value: 1.5 Ω Max.
If the specified value was Not obtained:
-- Check the wiring for an open, high resistance or short to ground or voltage.
-- Check the electrical harness connector for damage, corrosion, loose or broken terminals.
-- If necessary, repair the faulty wiring connection.
If the specified value was obtained:
-- Replace the Engine Control Module (ECM) -J623-.
-- Install the engine cover with air filter.
Final procedures
After the repair work, the following work steps must be performed in the following sequence:
- Check the DTC memory. Refer to DIAGNOSTIC MODE 03 - READ DTC MEMORY .
- If necessary, erase the DTC memory. Refer to DIAGNOSTIC MODE 04 - ERASE DTC MEMORY .
- If the DTC memory was erased, generate readiness code. Refer to READINESS CODE .
NO RELATED
Use the Manual With the Right Hardware
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.