Massey Ferguson 3361.04 – Engine Control Unit (ECU): DEF Injector Voltage Issue / DEF Dosing Valve High Side Short Circuit

The signal from the Diesel Exhaust Fluid (DEF) dosing injector is out of range low. The system has detected that the DEF dosing valve's high side has a short circuit to ground.

• 4710
• 7724S
• 5712SL
• Interim Tier 4 (2012-2015)
• 7722
• 7722S
• 7615
• 5613
• 5713SL
• 7720S
• 7716
• 7718
• T4
• 7715
• 5710SL
• 7726
• 7616
• 7618
• 5608
• 4708
• 7619
• 7626
• 7726S
• 7624
• 4707
• 4709
• 5711SL
• 7614
• 7718S
• 5610
• 7620
• 7719
• 7714
• 7716S
• T4 (2015-2021)
• 5612
• 7622
• 7720
• Tier 4 (2015-2021)
• 5611
• 7715S
• 5609
• 7724
• 5710 SL
• 5711 SL
• 5712 SL
• 5713 SL
• 7714 S
• 7715 S
• 7716 S
• 7718 S
• 7719 S
• 7720 S
• 7722 S
• 7724 S
• 7726 S

1. 1

   Wiring Harness Inspection: Trace the wiring harness from the Engine ECU to the DEF injector. Look for chafed wires, melted insulation, or pinch points where the wire may be grounding out against the chassis or engine block.

2. 2

   Connector Check: Disconnect the DEF injector and the ECU. Inspect the pins for corrosion, moisture, or damage that could cause a short.

3. 3

   Component Resistance Test: Test the resistance across the DEF injector terminals to determine if the internal solenoid has shorted out.

1. 1

   Disconnect Power

   Turn off the machine and disconnect the battery to prevent electrical spikes.

2. 2

   Repair Wiring

   If a short to ground was found in the harness during diagnostics, repair the damaged wire or replace the affected harness section.

3. 3

   Replace DEF Injector

   If the wiring tests good, the short is internal to the DEF dosing valve. Disconnect the electrical connector and the DEF fluid lines from the injector. Unbolt the injector from the exhaust/SCR system. Install the new DEF injector and torque to OEM specifications. Reconnect the fluid lines and electrical connector.

4. 4

   Clear Codes

   Reconnect the battery. Use a compatible diagnostic tool (such as AGCO WinEEM4 or JPRO) to clear the 003361.04 fault code from the Engine ECU.

5. 5

   Test Operation

   Run the engine and perform a forced DEF dosing test or SCR system test via the diagnostic tool to ensure the new valve is operating without voltage issues.