RLC 000158.18 – Control Software, Supply Voltage (ELX) Too Low

RLC 000158.18 (RLC 158.18)

Code: 000158.18

Shortcode: 158.18


This error code is triggered when the supply voltage (ELX) drops below 11.2 volts with engine speeds between 500 and 1500 rpm. This can indicate issues with the battery, electrical connections, or charging system under moderate engine load conditions.


When this error is detected, the control software may experience limited or no functionality, affecting the performance or operation of specific electronic control systems within the equipment.


  • Check Battery Condition:
    • Test the battery to ensure it is in good condition and capable of holding a charge. Replace the battery if it is found to be inadequate.
  • Inspect Electrical Connections:
    • Inspect all electrical connections, including those at the battery, alternator, and control software. Ensure they are clean, secure, and free from corrosion.
  • Verify Charging System Performance:
    • Check the alternator and voltage regulator to ensure they are functioning correctly and providing adequate charge to the battery. Replace any faulty components.
  • Monitor Electrical Load:
    • Ensure that the electrical load on the system is balanced and within acceptable limits during moderate engine speeds. Reduce unnecessary loads if necessary.


Maintaining proper supply voltage is crucial for the reliable operation of electronic control systems. Regular inspection and maintenance of the electrical system, including the battery and charging components, are essential to prevent voltage-related issues.

Control Units: John Deere

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