ECU 000029.08 – Secondary Throttle Signal Abnormal. John Deere Engine Control.

ECU 000029.08 (ECU 29.08)

Code: 000029.08

Shortcode: 29.08


The ECU 000029.08 (29.08) error code is triggered when the secondary throttle signal 2 is found to be abnormal in John Deere machinery. This condition suggests that the signal deviates significantly from expected parameters, potentially due to sensor failure, incorrect sensor calibration, or electrical issues in the wiring.


To manage this fault, the engine control system might engage a protective mode that limits engine functionality to stabilize operation and avoid damage due to erratic throttle behavior.


  • Evaluate Sensor and Wiring Integrity: Inspect the throttle sensor and its wiring for any signs of malfunction or damage that could disrupt normal signal generation.
  • Calibrate or Replace the Sensor: If the sensor is not functioning as expected, recalibrate it if possible, or replace it if recalibration does not resolve the issue.
  • System Reset and Functional Verification: After addressing the issue, reset the error codes and conduct extensive testing to ensure that the throttle signal remains stable and within normal operating parameters.


In the case of ECU 000029.08, it’s important to regularly update the firmware of the control systems, as outdated software can misinterpret sensor signals, leading to unnecessary throttle signal faults. Regular software updates can enhance sensor accuracy and system reliability.

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