SCC 000168.03 – SCC Unswitched Supply Voltage High

SCC 000168.03 (SCC 168.03)

Code: 000168.03

Shortcode: 168.03


This error code indicates that the Selective Control Unit (SCC) has detected an unswitched supply voltage above 18.0 V. High voltage can be caused by a malfunctioning voltage regulator, issues within the alternator, or external voltage sources impacting the system.


When this code is detected, the SCC will disable its functions, turning them off to prevent potential damage due to overvoltage.


Inspect Voltage Regulator:

  • Check the voltage regulator for proper operation. Replace if it is malfunctioning or not maintaining voltage within specified limits.

Examine Alternator Output:

  • Verify that the alternator is providing the correct voltage output. If the output is too high, repair or replace the alternator.

Check for External Voltage Sources:

  • Ensure that there are no external voltage sources improperly connected to the SCC circuit, which could cause the voltage to rise above 18.0 V.

Inspect Wiring and Connections:

  • Look for any signs of damaged wiring or poor connections that could affect voltage regulation. Repair or replace as necessary.

Monitor System Voltage:

  • Use a multimeter to continuously monitor the system voltage, ensuring it stays within the safe operating range.


High voltage issues can cause significant damage to electronic components. Immediate action is required to prevent further damage.

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