John Deere 168.04 – CRU / CSC: Battery Potential / Power Input 1 - Voltage Below Normal

Indicates a low voltage condition on the unswitched power supply circuit feeding a specific control module. When the voltage drops below the module's minimum operating threshold (7V for the Radio/CRU, 9V for most other modules like the CSC or CSM), the module will disable its functions or enter a safety mode to protect its internal circuitry from damage.

• 6110R
• 6120R
• 6130R
• 6145R
• 6155R
• 6175R
• 6195R
• 6215R
• 6230R
• 6250R
• 7210R–7290R
• 8225R–8400R
• 9470RT
• 9520RT
• 9570RT
• S660
• R4038
• 4930

1. 1

   Inspect the Battery & Alternator: Visually inspect the batteries and alternator for signs of damage, corrosion, or accumulated debris.

2. 2

   Test System Voltage: Use a multimeter to check the battery's resting voltage and the alternator's charging output.

3. 3

   Check Fuses: Inspect the fuses related to the specific module (e.g., Radio/CRU fuses in the cab load center, or ELX relay and Cab Suspension fuses).

4. 4

   Measure Voltage at the Module: Disconnect the harness at the affected module (CRU or CSC) and measure the voltage at the unswitched power input pins.

5. 5

   Inspect Wiring and Grounds: Check all wiring, harnesses, and chassis ground connections for the affected module. Look for chafed wires, loose pins, or corrosion.

1. 1

   Power Down

   Turn off the machine, remove the key, and disconnect the negative battery cable to ensure safety.

2. 2

   Clean Power Sources

   Clean the battery terminals, battery cables, and main chassis ground straps with a wire brush. Reconnect and tighten them securely.

3. 3

   Address Charging Issues

   If the battery or alternator failed the diagnostic load test, replace the faulty component.

4. 4

   Repair Harness/Connectors

   If the voltage drop is isolated to the module's harness, trace the unswitched power wire back to the fuse panel. Repair any broken, corroded, or chafed sections of the wire. Clean the module's connector pins with electronic contact cleaner.

5. 5

   Reassemble and Clear Codes

   Reconnect the module harness. Power on the tractor. The code may move to a "Stored" state automatically once proper voltage is detected. Cycle the key switch or use the CommandCenter™ display to clear the code.

6. 6

   Test Operation

   Verify that the radio turns on and functions (if CRU) or that the cab suspension levels properly (if CSC).