John Deere 523216.03 – SCO / SCC: Unswitched Supply Voltage High to SV I and SV II or Front SCVs

The system has detected that the unswitched supply voltage feeding the Selective Control Valves is above 18.0 Volts. Because high voltage can cause severe damage to the valves and their internal electronic components, the control software will typically disable the affected SCV functions to prevent further issues.

• 6110R
• 6120R
• 6130R
• 6145R
• 6155R
• 6175R
• 6195R
• 6215R
• 8225R
• 8235R
• 8245R
• 8260R
• 8270R
• 8285R
• 8295R
• 8310R
• 8320R
• 8335R
• 8345R
• 8360R
• 8370R
• 8400R
• 9230
• 9330
• 9430
• 9530
• 9630
• 8130
• 8230
• 8330
• 8430
• 8530

1. 1

   Monitor system voltage at the SCV inputs using a multimeter to verify if the voltage is spiking above 18.0V

2. 2

   Inspect the alternator and voltage regulator, as an overcharging system is the most common cause for voltage above 18V

3. 3

   Check wiring harnesses and connectors routing to the Front SCVs for signs of a short-to-power, damaged insulation, or corrosion

4. 4

   Verify that the power supply to the SCVs is stable and stays within the acceptable 9.0V to 16.0V range during operation

1. 1

   Test the Charging System

   Start the engine and measure the voltage at the batteries and the alternator output. If the system is charging at or above 18.0 Volts, replace the alternator (which houses the internal voltage regulator).

2. 2

   Repair Wiring Shorts

   If the alternator is outputting normal voltage (approx. 13.5V - 14.2V) but the SCV connector is receiving 18V+, trace the SCV wiring harness back to the SCO/SCC module to locate and repair the short-to-power.

3. 3

   Clean Connections

   Clean and secure any loose or corroded electrical connections at the SCV unit.

4. 4

   Replace the SCV Electronic Control Unit

   If the wiring and charging system are perfectly fine, or if a previous overvoltage event permanently damaged the SCV's internal circuitry, the Selective Control Valve Electronic Control Unit will need to be replaced.

5. 5

   Clear Codes

   Restart the engine and use the diagnostic monitor to clear the SCO/SCC codes. Operate the hydraulic valves to verify the code does not return.