Description:

This error code, SV1 000158.04, is triggered when the switched supply voltage to the Selective Control Valve Unit I (SV I) drops below 9.0 volts. This can be caused by electrical issues such as poor connections, faulty wiring, or issues within the vehicle’s power supply system.

Reaction:

When this error code is detected, the equipment may experience insufficient power to the Selective Control Valve Unit I, leading to potential malfunctions or non-responsiveness of the hydraulic functions controlled by this valve unit.

Recommendations:

• Inspect Electrical Connections:
  • Check all electrical connections to the SV I for any signs of corrosion, loose connections, or damaged wiring. Secure or replace as necessary.
• Test Voltage Levels:
  • Measure the voltage at the SV I to confirm it is below 9.0 volts. If the voltage is too low, trace back to identify the source of the undervoltage condition.
• Vehicle Load Center (VLC) Diagnostics:
  • Perform diagnostics on the VLC control unit as it is the voltage source for the wake-up circuit. Ensure that the VLC is functioning correctly and that there are no associated fault codes that could be causing the low voltage.
• Inspect Power Supply:
  • Verify the integrity of the vehicle’s power supply system, including the battery and alternator, to ensure they are operating within normal parameters.
• Update Software:
  • Ensure all relevant control unit software is up-to-date to avoid any software-related voltage regulation issues.

Note:

This code, along with other 000158.XX codes, may also appear in other control units. It is crucial to perform a comprehensive diagnostic of the VLC control unit first, as it is the primary voltage source. Checking the VLC can often resolve multiple related error codes simultaneously. Additionally, ensure regular maintenance and updates to the vehicle’s electrical and diagnostic systems to prevent recurring issues.