BCU 000190.02 – Crankshaft Speed Sensor Open Circuit. John Deere System Advisory.

BCU 000190.02 (BCU 190.02)

Code: 000190.02

Shortcode: 190.02


Error code BCU 000190.02 occurs when the Basic Control Unit (BCU) of a John Deere vehicle detects an open circuit in the crankshaft speed sensor. This diagnostic trouble code is specifically recognized when an attempt is made to activate a function at a nonexistent input address (BCU030) in the BCU. The issue indicates that there is a discontinuity or break in the electrical connection of the crankshaft speed sensor, which prevents it from transmitting essential engine speed data to the control unit.


The BCU may issue a fault alert, and depending on the system’s design, this might affect the engine’s operation, potentially preventing the engine from starting or affecting its performance due to lack of critical speed data.


  • Check Input Address Settings: First, verify that the correct input address settings are used. An incorrect address setting can trigger this error even if the sensor and circuit are otherwise functional.
  • Inspect Crankshaft Speed Sensor and Wiring: Examine the crankshaft speed sensor for signs of damage or wear. Check the wiring and connectors for breaks, corrosion, or loose connections that could result in an open circuit.
  • Test Sensor and Circuit Continuity: Use a multimeter to test for continuity in the crankshaft speed sensor circuit. This will help confirm the presence of an open circuit.
  • Repair or Replace Faulty Components: Repair any detected wiring issues or replace damaged parts to restore the integrity of the sensor circuit.
  • Reset the BCU and Clear Diagnostic Codes: After completing repairs or adjustments, reset the BCU to clear any stored fault codes. Conduct a test run to ensure the crankshaft speed sensor is now operating correctly and that the engine is performing well.


Maintaining accurate readings from the crankshaft speed sensor is crucial for proper engine management and performance. Regular inspections and prompt attention to issues like open circuits can help avoid engine performance problems and ensure the longevity and reliability of your John Deere equipment. Addressing these issues as they arise ensures that the vehicle remains operational and efficient.