Deutz-Fahr 654 – ECM: Cable Break in Injector 4

An electrical open circuit has been detected in the wiring for the fuel injector of cylinder number four. The Engine Control Module (ECM) has identified a loss of continuity, which could be caused by a broken wire, a disconnected or damaged connector, or an internal failure within the injector's solenoid coil. This open circuit prevents the ECM from sending the electrical pulse needed to activate the injector, resulting in improper operation, a loss of fuel delivery to that cylinder, and negatively affecting overall engine performance.

• TCD 2.9
• TCD 3.6
• D4D 140B
• D2.9
• 2012

1. 1

   Perform a visual inspection of the wiring harness leading to injector 4 for chafing, cuts, melting, or rodent damage. Ensure connectors are securely seated and terminals are free of corrosion, dirt, oil, or spread pins.

2. 2

   Conduct a wiggle test on the wiring harness and connector for injector 4 while the engine is running (if possible) to check for intermittent connections.

3. 3

   Check for voltage at the injector connector (Key ON, Engine OFF) to ensure power supply from the ECM. Disconnect the wiring harness and use a multimeter (negative to ground, positive to terminals); one terminal should show close to battery voltage (~12V).

4. 4

   Test the injector solenoid resistance with a multimeter (Ignition OFF). Normal resistance is typically 0.5 to 2.0 ohms; an 'OL' (Over Limit) reading indicates an open internal coil.

5. 5

   Check harness continuity between the ECM connector and the injector connector. Disconnect the battery first, then the main ECM connector, and test each wire individually. Also test for any shorts to ground between each injector wire and a known good engine ground.

1. 1

   Isolate machine

   Park the machine on level ground, engage the parking brake, turn off the engine, and disconnect the negative battery terminal to prevent electrical shorts.

2. 2

   Access injector 4

   Remove any engine covers, air intake piping, or other components obstructing access to the injector and its wiring.

3. 3

   Repair or replace wiring

   If diagnostic checks revealed a broken wire or damaged connector, repair or replace the faulty section of the harness. If the entire harness is damaged, replace it as a complete unit. Ensure all connections are clean, secure, and insulated.

4. 4

   Replace fuel injector

   If the injector solenoid tested open-circuited, replace the injector. Clean the area, disconnect high-pressure and return lines, remove the hold-down bolt and clamp, and remove the old injector (using a slide hammer or specialized puller if seized). Install the new injector with a new copper sealing washer and any other required seals. Torque the hold-down bolt and line fittings to manufacturer specifications.

5. 5

   Final assembly and test

   Reconnect the injector wiring harness, reinstall removed components, and reconnect the battery. Prime the fuel system if required, start the engine to check for leaks, and use a diagnostic tool to clear the fault code.