Deutz-Fahr 572 – ECU: Injector 5 Power Interruption

The Engine Control Unit (ECU) has detected a loss of electrical continuity (current below normal or open circuit) in the circuit for the fuel injector corresponding to the fifth cylinder in the engine's firing order. This power interruption prevents the injector from operating properly, which negatively affects engine performance. The issue is typically caused by a broken wire, a loose or corroded connector, or an internal failure within the injector's solenoid coil.

• TCD 2012
• TCD 2013
• TCD 3.6
• Genie lifts

1. 1

   Visually inspect the wiring harness between the ECU and injector 5 for chafing, cuts, or heat damage from exhaust components.

2. 2

   Check the electrical connectors at the injector and ECU for dirt, moisture, corrosion, or pushed-out pins.

3. 3

   Use a multimeter to check for an open circuit between the ECU connector and the injector connector (a reading of 'OL' indicates a broken wire).

4. 4

   Check for a short to ground by testing continuity between each wire in the injector circuit and the engine block or chassis ground ('OL' is expected).

5. 5

   Measure the injector coil resistance across its two terminals (common rail injectors should read 0.4-0.8 ohms; 'OL' indicates a broken internal coil).

6. 6

   Use a diagnostic scanner to read the FMI code (FMI 5 indicates open circuit) and perform an injector cut-out test to confirm the misfire.

1. 1

   Repair or replace wiring

   If a broken wire is found, repair it using a sealed connector or solder with heat shrink tubing. If the harness has extensive damage, replace the Engine ECM Harness.

2. 2

   Clean electrical connectors

   If connectors are dirty or corroded, clean the pins and sockets with electrical contact cleaner and ensure a secure connection upon reassembly.

3. 3

   Depressurize fuel system

   If the injector coil is faulty and requires replacement, safely depressurize the common rail fuel system according to manufacturer instructions before proceeding to prevent injury from high-pressure fuel.

4. 4

   Remove faulty injector

   Clean the area around the injector, disconnect the electrical connector and fuel lines (cap them immediately), remove the hold-down bolt or clamp, and carefully extract the injector. Use a slide hammer if it is seized.

5. 5

   Install new injector

   Clean the injector bore in the cylinder head, install a new sealing washer and O-rings, insert the new injector, and torque the hold-down bolt to the manufacturer's specification. Reconnect fuel lines and electrical connectors.

6. 6

   Finalize repair

   Bleed the fuel system if required by the manufacturer, clear the fault codes with a diagnostic scanner, start the engine, and verify there are no fuel leaks or returning fault codes.