Bank 2 Fuel Injectors, Checking
Bank 2 Fuel Injectors, Checking
The following test procedure is used to diagnose all fuel injectors controlled by the Engine Control Module (ECM) (J623).
Special tools, testers and auxiliary items required
• Multimeter.
• Diode test lamp (12V).
• Wiring diagram.
Test requirements
• The Engine Control Module (ECM) (J623) 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 Clean Working Conditions.
Test procedure
- Perform a preliminary check to verify the customers complaint. Refer to => [ Preliminary Check ] Preliminary Check.
Start diagnosis
- Remove the intake manifold.
- Disconnect the Fuel Injector electrical harness connectors - 5,6,7,8 - 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: 12.0 to 20.0 ohms (at approx. 20 °C)
If the specified value was not obtained:
- Replace the faulty Fuel Injector
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
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.
If the manufacturers test box is not being used, perform the following step.
- Remove the Motronic Engine Control Module (ECM) (J623). Refer to => [ Engine Control Module, Removing and Installing ] Engine Control Module, Removing and Installing.
- Using a multimeter, check the electrical harness connector terminals of the Fuel Injector to be tested to the Motronic Engine Control Module (ECM) (J623) electrical harness connector terminals for resistance.
Specified value: 1.5 ohms Max.
If the specification is not obtained:
- Check the wiring for an open circuit, a short circuit to each other, Battery (+), or Ground (GND).
- Check the electrical harness connector for damage, corrosion, loose or broken terminals.
- If necessary, repair the faulty wiring connection.
If no malfunction is detected in the wiring:
- Erase the DTC memory. Refer to => [ Diagnostic Mode 04 - Erase DTC Memory ] Diagnostic Mode 04 - Erase DTC Memory.
- Perform a road test to verify repair.
If the DTC does not return:
Repair complete, Generate readiness code. Refer to => [ Readiness Code ] Readiness Code.
- End diagnosis.
If the DTC returns and no malfunction is found in the wiring and voltage supply was OK:
- Replace the Motronic Engine Control Module (ECM) (J623). Refer to => [ Engine Control Module, Replacing ] Engine Control Module, Replacing.
Assembly is performed in the reverse order of the removal, note the following:
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 ] Readiness Code.