Massey Ferguson 655.14 – Engine Control Unit (ECU): Injector Number 5 Short Circuit (ECU)

The engine control system has detected a short circuit in the electrical circuit for fuel injector number 5. This means electrical current is bypassing the normal load path. It can be caused by a wiring harness shorting to ground (like rubbing against the engine block or rocker arm), wires shorting to each other, or an internal short within the injector's electromagnetic coil itself.

• 4710
• 7724S
• Interim Tier 4 (2012-2015)
• 7722S
• 7722
• 7615
• 7720S
• 7716
• 7718
• 7726
• 7715
• 7616
• 7618
• 4708
• 7619
• 7626
• 7726S
• 7624
• 4707
• 4709
• 7614
• 7718S
• 7620
• 7719
• 7714
• 7716S
• T4 (2015-2021)
• 7622
• 7720
• Tier 4 (2015-2021)
• 7715S
• 7724
• 7714S
• 7719S
• 8650
• 8660
• 8670
• 8680
• 8690
• 8727
• 8730
• 8732
• 8735
• 8737

1. 1

   Visual Harness Inspection: Trace the wiring harness from the ECU to Injector #5. Look closely for chafing, melted insulation, or areas where the wire might be rubbing against the rocker arm or engine block (a highly common cause of intermittent shorts to ground).

2. 2

   Connector Check: Disconnect the electrical connector at Injector #5. Inspect for corrosion, bent pins, or fluid intrusion (oil/diesel) inside the plug.

3. 3

   Injector Resistance Test (Ohm Test): Using a multimeter, measure the resistance across the two pins on Injector #5. Compare this reading to a known good injector on the same engine (e.g., Injector #4). If the resistance is significantly lower or shows continuity to the injector's metal body, the injector is internally shorted and must be replaced.

4. 4

   Harness Continuity Test: With the ECU and injector disconnected, test the harness wires for continuity to ground and to each other. If a short is found in the harness, the wiring is the culprit.

1. 1

   Turn off the tractor and disconnect the negative battery terminal.

2. 2

   Remove the engine covers and valve cover

   (if required on your specific engine model) to access the fuel injectors and wiring harness.

3. 3

   Perform the diagnostic tests above.

4. 4

   If the wiring is damaged:

   Repair the damaged section using proper automotive wire and heat shrink. Ensure the harness is re-routed and secured away from moving parts or extreme heat sources.

5. 5

   If the injector is internally shorted:

   Thoroughly clean the area around Injector #5 to prevent debris from falling into the cylinder. Disconnect the high-pressure fuel line and the leak-off (return) line. Remove the injector hold-down clamp/bolt. Carefully extract the injector. Install the new injector using a new copper sealing washer/O-ring. (Note: It is highly recommended to replace the connector tube at the same time). Reinstall the hold-down clamp and torque to OEM specifications. Reconnect the fuel lines and electrical connector.

6. 6

   Reconnect the battery.

7. 7

   Prime/bleed the fuel system.

8. 8

   Use a diagnostic scan tool to clear the 000655.14 fault code from the ECU.

9. 9

   Start the engine, check for fuel leaks, and verify smooth operation.