John Deere 656.18 – Engine Control Unit (ECU): Injector Number 6 Not Responding or Fuel Injector #6 Flow Very Low

Injector #6 is not responding as expected or has very low fuel flow. The Engine Control Unit (ECU) logs this code when it detects that the current supplied to the injector is incorrect, or the fuel flow is below the specified threshold. According to the SAE J1939 standard, SPN 656 identifies the fuel injector for cylinder #6, and FMI 18 indicates a moderately severe failure mode.

• 6110M
• 6120M
• 6130M
• 6145M
• 6155M
• 6175M
• 6195M
• 6110R
• 6120R
• 6130R
• 6145R
• 6155R
• 6175R
• 6195R
• 6215R
• 8235R
• 8245R
• 8260R
• 8270R
• 8285R
• 8295R
• 8310RT
• 8335RT
• 8345R
• 8360RT
• 8400R
• 9540
• 9560
• 9580
• 9640
• 9660
• 9680
• 4930
• 350GLC
• 380GLC
• 644K
• 724K
• 670G
• 672G
• 770G
• 1270E
• 1470E

1. 1

   Check for ECU software updates (DTAC solution 117409 identifies nuisance DTCs 651.18 through 656.18 that can lead to misdiagnosis)

2. 2

   Inspect the electrical connector directly at Injector #6 for corrosion or looseness caused by engine vibration and heat

3. 3

   Test the injector wiring and solenoid for high or low resistance to rule out electrical faults

1. 1

   Update ECU Software

   If applicable to your specific machine's DTAC bulletins, flash the Engine ECU with the latest software to rule out a false code.

2. 2

   Inspect the Harness

   Visually inspect the wiring harness leading to cylinder #6 for chafing, melting, or loose pins.

3. 3

   Test the Injector

   If the wiring is intact and the software is up to date, the fault indicates that the injector has mechanically failed or the flow limiter is closed.

4. 4

   Replace the Injector

   Remove and replace Fuel Injector #6. Note: Some aftermarket suppliers recommend replacing the entire set of injectors to ensure optimal engine performance, as mixing genuine and aftermarket parts can cause differences in atomization and fuel output.

5. 5

   Clear Codes

   Install the new injector with fresh O-rings, bleed the fuel system if required by the manual, clear the ECU codes, and test run the machine to ensure the code does not return.