Case IH 17522 (F-1761-14) - ECU – ECU: Sensor reports a system error for the Urea level

The Diesel Exhaust Fluid (DEF / Urea) tank level sensor is reporting a supply signal that is either above the upper limit or below the lower limit, or that the warning threshold for the urea tank level has been exceeded. This prevents the Selective Catalytic Reduction (SCR) system from accurately monitoring the DEF level, which can eventually lead to engine derating.

• VESTRUM CVX
• Magnum
• Steiger
• Puma
• Optum
• Axial-Flow 7120
• Axial-Flow 7230
• Axial-Flow 8230
• 621G
• 821F
• 921F
• 1021G
• T7
• T8

1. 1

   Check the sensor connector, wiring harness, and pins for damage, corrosion, or short circuits.

2. 2

   Verify the accuracy of the Urea tank level and temperature sensor readings using a diagnostic tool.

3. 3

   Check the DEF tank for dirt, debris, or DEF crystallization.

4. 4

   Ensure the DEF tank vent hose is not clogged and clean all inline main and nozzle screens in the DEF system.

1. 1

   Drain the Tank

   Completely drain the DEF tank to prevent spills and remove any contaminated fluid.

2. 2

   Disconnect the Unit

   Unplug the electrical wiring harness connector from the DEF sending unit.

3. 3

   Remove the Sensor Assembly

   Unbolt/unscrew the DEF header unit from the top of the DEF tank and carefully extract the integrated sensor assembly (which includes the level sensor, temperature sensor, and pickup tubes).

4. 4

   Clean the Tank

   If contamination or crystallization was found, thoroughly clean the inside of the tank and the mounting surface.

5. 5

   Install the New Unit

   Insert the replacement DEF sending unit into the tank, ensuring the seals are properly seated, and secure it.

6. 6

   Reconnect and Refill

   Reconnect the electrical harness and fluid lines. Refill the tank with fresh, high-quality Diesel Exhaust Fluid.

7. 7

   Clear Codes

   Use a dealer laptop or compatible diagnostic tool to clear the ECU fault codes and reset the SCR system.