John Deere 3361.06 – Engine Control Unit (ECU): DEF Dosing Injector Circuit Has Low Resistance

The Engine Control Unit has detected that the electrical resistance in the Diesel Exhaust Fluid (DEF) dosing injector circuit is too low. This condition specifically indicates a short circuit to ground within the injector's wiring or the injector solenoid itself, preventing the injector from properly metering and injecting DEF into the exhaust stream, which will likely cause the engine to derate or initiate protective shutdown measures.

• 5085E
• 5090E
• 5090EL
• 5100E
• 5090M
• 5100M
• 5100MH
• 5100ML
• 5115M
• 6110M
• 6120M
• 6130M
• 6145M
• 6155M
• 6175M
• 6195M
• 6110R
• 6120R
• 6130R
• 6145R
• 6155R
• 6175R
• 6195R
• 6215R
• 8245R
• 8400R
• 9470RT
• 9520RT
• 9570RT
• 6105M
• 5085M
• 5095M
• 5105M
• 5115ML
• 744K
• 750K
• 824K
• 844K
• 850K
• 1050K
• 130G
• 135G
• 160G LC
• 180G LC
• 190GW
• 245G
• 345G LC
• 670G
• 870G

1. 1

   Inspect the electrical connector directly at the DEF dosing injector for melting, corrosion, or looseness caused by vibration and extreme exhaust heat.

2. 2

   Use a digital multimeter to measure the resistance levels within the DEF injector circuit. Test the low side of the circuit for continuity to ground to pinpoint the exact location of the short.

3. 3

   Trace the wiring harness from the DEF injector back to the ECU. Look for chafed wires, melted insulation, or pinched harnesses that are shorting against the machine's chassis or ground.

4. 4

   If the wiring harness tests fine, plug in a known-good test dosing valve (if available) to see if the short circuit clears. If the code goes inactive, the original DEF dosing injector is internally shorted.

1. 1

   Resolve Wiring Issues

   If the diagnostic tests revealed a short in the harness, repair or replace the damaged section of the wiring circuit to restore proper electrical isolation.

2. 2

   Remove the Defective Injector

   If the injector itself is internally shorted, disconnect the battery power. Carefully detach the electrical connector and the DEF supply line from the injector. Remove the mounting hardware (usually flanged screws) and pull the injector from the exhaust aftertreatment housing.

3. 3

   Install the New Injector

   Clean the mounting surface. Always use a new DEF injector gasket (do not reuse the old one). Align the new DEF dosing injector and securely attach the fittings.

4. 4

   Torque to Spec

   Use a torque wrench to tighten the mounting bolts to the manufacturer's specified torque levels to prevent exhaust leaks.

5. 5

   Reassemble and Test

   Reconnect the DEF supply line and the electrical connector. Reconnect the machine's power supply.

6. 6

   Reset ECU

   Clear the 003361.06 fault code from the ECU using a diagnostic scan tool. Run the engine and perform a forced manual DEF dosing test or a parked regeneration to ensure there are no leaks and the system is dosing correctly.