+352 27 63 53 92

customer-service@partao.com
3516.01

John Deere 3516.01 – ECU: Aftertreatment DEF Concentration Extremely Low

Issue description

Triggered when the Diesel Exhaust Fluid (DEF) quality/concentration sensor detects that the fluid in the DEF tank is below the acceptable concentration threshold. Often caused by an internal failure of the DEF concentration sensor itself reading the fluid incorrectly, rather than bad fluid.

Applies to these machines

  • 5085E
  • 5090E
  • 5090EL
  • 5100E
  • 5090M
  • 5100M
  • 5100MH
  • 5100ML
  • 5115M
  • 6110M
  • 6120M
  • 6130M
  • 6145M
  • 6155M
  • 6175M
  • 6195M
  • 6110R
  • 6120R
  • 6130R
  • 6145R
  • 6155R
  • 6175R
  • 6195R
  • 6215R
  • 330G
  • 331G
  • 332G
  • 333G
  • 210GLC
  • 350GLC
  • 8270R
  • 8370R
  • 9520R

Check the cause

  1. Test the DEF fluid from the tank using a DEF refractometer (standard ISO 22241-certified DEF should read approximately 32.5% concentration).

  2. Connect a diagnostic tool to compare the machine's live DEF concentration reading against the refractometer reading. A significantly lower live reading indicates an internal sensor fault.

  3. Ensure the DEF tank is not frozen and verify the sensor is not obstructed by debris or crystallized DEF.

  4. Inspect the electrical wiring harness and grounding to the DEF header for any damage.

Repair steps

  1. Thaw DEF tank

    Thaw out the DEF tank if the machine has been operating in freezing conditions.

  2. Remove covers and guards

    Remove any step assemblies, guards, or covers located over the DEF tank to gain access to the top of the tank.

  3. Disconnect lines and connectors

    Disconnect the electrical connectors and fluid/coolant lines from the DEF header assembly.

  4. Remove faulty header

    Remove the faulty DEF header from the tank.

  5. Install new header

    Install the new DEF Tank Header Assembly and reconnect all lines and harnesses.

  6. Reinstall covers

    Reinstall the step assembly and any protective covers.

  7. Purge coolant system

    Start the machine and perform a header coolant purge procedure to remove air from the system.

  8. Verify repair and clear codes

    Verify the repair by checking live sensor data, and clear the active ECU 3516.01 codes using your diagnostic tool.

Parts you might need

(5)

  • DEF Tank Header Assembly

    AT491599

    Fits models like the 350GLC Excavator. Often superseded by DZ120744.

  • DEF Tank Header Assembly

    DZ120744

    Supersedes AT491599.

  • DEF Tank Header Assembly

    AT491606

    Variation depending on specific machine's PIN/Serial Number.

  • DEF Tank Header Assembly

    AT491600

    Variation depending on specific machine's PIN/Serial Number.

  • Diesel Exhaust Fluid (DEF)

    SWDEF025

    John Deere Diesel Exhaust Fluid, 2.5 Gallon. Any generic ISO 22241-certified DEF can also be used.

Get help to fix this fault by requesting a quote

Browse other John Deere codes