RLC 000158.01 – Control Software, Supply Voltage (ELX) Too Low

RLC 000158.01 (RLC 158.01)

Code: 000158.01

Shortcode: 158.01


This error code is triggered when the supply voltage (ELX) drops below 12.5 volts while the engine speed is above 1500 rpm. Low voltage levels can indicate issues with the charging system, battery, or electrical connections.


When this error is detected, the control software may experience limited or no functionality, leading to reduced performance or failure of specific electronic control systems within the equipment.


  • Inspect the Charging System:
    • Verify the alternator’s output voltage to ensure it is charging the battery properly. Replace the alternator if it is undercharging.
  • Check Battery Health:
    • Test the battery to ensure it holds a charge and is in good condition. Replace the battery if it is old or unable to maintain adequate voltage.
  • Examine 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 Belt Tension:
    • Check the tension of the alternator belt. A loose or worn belt can cause inadequate alternator performance.
  • Monitor Electrical Load:
    • Reduce unnecessary electrical loads and check for any components that may be drawing excessive power.


Consistently low supply voltage can cause long-term damage to the control software and other electronic components. Regular maintenance of the electrical system is crucial to prevent such issues.

Control Units: John Deere

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