John Deere 4367.06 – ECU: The DEF Reverse Flow Solenoid Valve High Amps

Resistance in the DEF Dosing Unit Reversing Valve (Return Valve) circuit is too low, or the current is above normal, typically pointing to a short to ground. This prevents the reversing valve from functioning properly, disrupting the DEF dosing process and the system's ability to purge DEF back into the tank when the machine is shut off.

• 5085E
• 5090E
• 5090EL
• 5100E
• 5090M
• 5100M
• 5100MH
• 5100ML
• 5115M
• 6110M
• 6120M
• 6130M
• 6145M
• 6155M
• 6175M
• 6195M
• 6110R
• 6120R
• 6130R
• 6145R
• 6155R
• 6175R
• 6195R
• 6215R
• Final Tier 4 (FT4) equipment

1. 1

   Inspect the DEF pump electrical connector for DEF fluid intrusion or heavy corrosion, which indicates an internal pump failure.

2. 2

   Inspect the wiring harness leading to the DEF dosing unit reversing valve for physical damage, chafing, or a short to ground.

3. 3

   Measure the resistance of the reversing valve circuit using a multimeter to confirm the short.

4. 4

   Perform a DEF pump test using John Deere Service Advisor (if available) to verify if the system can build pressure and actuate the valve.

1. 1

   Power Down

   Disconnect the machine's batteries before servicing the emissions system to prevent further electrical shorts.

2. 2

   Examine and Clean

   Disconnect the DEF pump electrical connector. If fluid is present, thoroughly clean and dry the harness side of the connector using electrical contact cleaner.

3. 3

   Replace the DEF Pump

   If the pump has leaked internally into the electrical connector (causing the short to ground), the entire DEF Dosing Unit / Pump must be replaced.

4. 4

   Repair Wiring

   If the pump is dry but the harness is damaged, repair or replace the affected section of the wiring harness.

5. 5

   Reset and Test

   Reconnect the batteries. Use a diagnostic tool to reset the ECU and clear the fault code. Run the machine and monitor the system (or force a regeneration) to ensure the reversing valve operates correctly and the code does not return.