Massey Ferguson 3031.16 – Engine ECU (EEM - Electronic Engine Module): Issue With The Temperature Of The DEF Tank Temperature Sensor. (ECU)

The Electronic Engine Module (EEM) has detected that the temperature value being reported by the Diesel Exhaust Fluid (DEF / AdBlue) tank temperature sensor is implausible, out of range, or indicating an overheating condition.

• 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

1. 1

   Check for a loose contact in the DEF tank temperature sensor wiring harness. Inspect the connector for corrosion, DEF crystallization, or moisture.

2. 2

   Test the sensor wiring for continuity and ensure there are no shorts to ground or defective wires leading back to the EEM.

3. 3

   If the DEF tank is surrounded by a protective cover or shield, remove the cover to inspect the sensor unit and ensure accurate temperature measurement.

4. 4

   Check the DEF fluid condition. If the fluid has overheated or become contaminated, it can trigger implausible readings. Overheated or degraded AdBlue must be drained and replaced with fresh fluid.

1. 1

   Clear the Log

   Connect your diagnostic service tool (e.g., WinEEM3s/WinEEM4 or AGCO EDT). Save the current error log, then erase the active code to see if it immediately returns upon key-on.

2. 2

   Access the Sensor

   Locate the DEF tank header unit (which houses the pump module, fluid pickup, and the level/quality/temperature sensors). Clean the area around the tank neck thoroughly to prevent dirt from entering the tank.

3. 3

   Disconnect and Test

   Disconnect the electrical harness from the DEF sensor head. Use a multimeter to verify the 5-volt reference supply from the Engine Module.

4. 4

   Replace the Sensor

   If the wiring tests good but the fault persists, the sensor itself is defective. On most modern Massey Ferguson systems, the temperature sensor is integrated into the main DEF tank sensor/header unit. Remove the retaining ring/bolts, pull the old sensor unit out, and install the new one, ensuring the O-ring is properly seated to prevent contamination.

5. 5

   Refill and Prime

   If the tank was drained, refill with fresh 32.5% urea DEF/AdBlue.

6. 6

   Clear Derate

   Turn the ignition ON, engine OFF. Clear the fault codes via the diagnostic tool. Start the engine and verify that the warning lamp extinguishes and the engine power derate is lifted.