Deutz-Fahr 167 – ECU: Short Circuit in Injector 5

The Engine Control Module (ECU) has detected an electrical fault, specifically a short circuit, within the electrical circuit for the fuel injector of cylinder number 5. This underlying condition can stem from a malfunction in the injector's internal coil, the wiring harness, or the ECU's injector driver, leading to symptoms such as rough idling, reduced engine power, increased fuel consumption, or engine misfires.

• TCD 2.9
• TCD 3.6
• TCD 4.1
• TCD 6.1
• TCD 7.8
• 1011 Series
• 2011 Series

1. 1

   Perform a visual inspection of the wiring harness and connectors between the ECU and injector 5 for chafing, corrosion, melting, loose connections, or oil/dirt on the pins.

2. 2

   Check connector integrity by disconnecting injector 5 and the ECU to inspect pins and terminals for damage, corrosion, or being pushed back into the housing.

3. 3

   Perform a wiring harness continuity and short circuit test using a multimeter to check for continuity, short to ground, short to power, and short between the two injector wires.

4. 4

   Conduct an injector resistance test with a multimeter set to Ohms across the disconnected injector terminals. A zero or near-zero reading indicates an internal short circuit.

5. 5

   Perform an injector swap test by swapping injector 5 with another cylinder (e.g., cylinder 4), clearing codes, and running the engine to see if the fault follows the injector or remains on cylinder 5.

1. 1

   Disconnect power

   Disconnect the battery before starting any repair work to ensure safety.

2. 2

   Access the injector

   Remove any components obstructing access to injector 5, such as engine covers or high-pressure fuel lines. Use compressed air to clean the area around the injector to prevent debris from falling into the cylinder.

3. 3

   Address wiring faults

   If a wiring issue was identified during diagnostics, repair or replace the damaged section of the harness. Use a harness repair kit or a new harness for extensive damage, ensuring all connections are clean and secure.

4. 4

   Replace the injector

   If the injector is confirmed faulty, disconnect the fuel line and electrical connector, remove the hold-down clamp/bolt, and carefully extract the old injector. A specialized removal tool may be necessary if it is seized. Clean the injector bore, install the new injector with new seals, torque the clamp to manufacturer specifications, and reconnect the lines.

5. 5

   Final reassembly and verification

   Reassemble all previously removed components. Reconnect the battery, clear the fault codes from the ECU using a diagnostic tool, and start the engine to verify that the repair has resolved the issue.