CAB 000158.04 – Low Voltage in CAB Switched Supply

CAB 000158.04 (CAB 158.04)

Code: 000158.04

Shortcode: 158.04


Error code CAB 000158.04 is triggered when the CAB control unit identifies a lower than expected voltage in the switched battery supply from the Cab Load Center wake-up circuit. Low voltage in this critical circuit can impair the performance and reliability of the CAB system, potentially leading to inadequate system responses or operational failures.


Due to the low voltage condition, the system imposes a limited functionality mode to prevent undue stress on electrical components and ensure operational safety under compromised power conditions.


  • Thorough Inspection of Wiring and Connectors: Begin with a detailed check of all wiring and connectors involved in the CAB switched supply. Look for signs of wear, loose connections, or corrosion that could be causing voltage drops.
  • Verify Battery and Charging System Health: Ensure that the battery is in good condition and the charging system is operating effectively. A failing battery or alternator can result in consistently low voltage outputs.
  • Assess Voltage Output at Cab Load Center: Measure the voltage output directly at the Cab Load Center during different operational states to determine if there is a significant drop under specific conditions.
  • Replace or Repair Faulty Electrical Components: If any components such as voltage regulators, relays, or fuses are found to be defective, replace them promptly to restore proper voltage levels.
  • Reset and Recalibrate the CAB System: After addressing the issues, reset the control unit to clear any fault modes. Recalibrate the system to ensure all components are functioning correctly under the adjusted voltage conditions.


Monitoring and maintaining the electrical infrastructure of CAB systems are crucial to avoid voltage issues. Implementing routine diagnostics and preventive maintenance schedules can help catch and correct voltage discrepancies before they lead to larger system problems. Regular updates and checks ensure that all components remain in optimal working condition, thereby extending the lifespan and efficiency of the equipment.

Control Units: John Deere

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