Massey Ferguson E1761.01 – Engine Control Unit (ECU): DEF Tank Level Low / DEF Tank Empty

The Diesel Exhaust Fluid (DEF) level in the tank has dropped to an extremely low or critical level. If ignored, this emission-related fault will eventually trigger an operator inducement system, resulting in severe engine power derate or speed reduction.

• 7616
• 5612
• 7622
• Interim Tier 4 (2012-2015)
• 7614
• 5611
• 7615
• 5610
• 5613
• 7620
• 5609
• 7618
• 5608
• 7619
• 7626
• 7624
• Massey Ferguson 5400 Series
• 4707
• 4708
• 4709
• 4710

1. 1

   Manually verify the actual DEF level in the tank (most common cause is an empty tank)

2. 2

   Ensure the DEF is not contaminated, cloudy, or frozen (use only high-quality ISO 22241-compliant DEF)

3. 3

   Inspect the wiring harness and connectors going to the DEF tank level sensor for corrosion, loose connections, or damaged wires

4. 4

   Inspect the sensor area for DEF crystallization buildup, which can cause the float or ultrasonic sensor to stick

5. 5

   Use a diagnostic tool to verify CAN communication between the DEF tank sensor and the engine ECU

1. 1

   Refill the Tank

   Fill the DEF tank with fresh, uncontaminated Diesel Exhaust Fluid.

2. 2

   Clear the Code

   Turn the ignition off for a minimum of 60 seconds, then turn it back on. Connect a diagnostic tool, save the error log, and erase the fault codes. Restart the ECU and run the engine to see if the fault returns.

3. 3

   Clean the Sensor/Header

   If the tank is full but the code persists, remove the DEF header unit from the top of the tank. Clean any crystallized DEF from the sensor using warm distilled water.

4. 4

   Replace the Sensor

   If the wiring is intact and cleaning does not restore the sensor's function, the DEF tank level sensor has failed internally.

5. 5

   Install New Component

   Install the new DEF level sensor/header assembly. Ensure the mounting bolts are torqued to spec and all hoses/electrical connectors are securely reattached.

6. 6

   Final Verification

   Clear the codes again and run the tractor through a standard driving cycle to ensure the ECU registers the correct fluid level and the warning lights remain off.