John Deere 2602.01 – CCU or SCC: Hydraulic Clean Oil Reservoir Level Very Low

Triggered when the hydraulic oil level switch detects that the oil level in the clean oil reservoir is critically low, which could severely impact machine operation. It often means that the differential case has been depleted of oil and is no longer supplying the clean oil reservoir.

• 6110R
• 6120R
• 6130R
• 6145R
• 6155R
• 6175R
• 6195R
• 6215R
• 9330
• 9430
• 9530
• 9630
• 8310RT
• 8335RT
• 8360RT
• 8130
• 8230
• 8330
• 8430
• 8530
• 7R Series
• 8R Series
• 4940 SP Sprayer

1. 1

   Verify Fluid Levels: Park the machine on a level surface and manually check the hydraulic oil level according to the Operator's Manual procedure.

2. 2

   System Refill Test: Increase the engine RPM and limit hydraulic use to see if it allows the clean oil reservoir to refill from the differential case.

3. 3

   Inspect for Leaks: Check the transmission, differential, and hydraulic lines for external leaks that could cause fluid depletion.

4. 4

   Pump Failure Check: Verify if the steering pump or the charge pump has failed during vehicle operation, which can prevent oil from circulating properly.

5. 5

   Sensor/Wiring Inspection: If the fluid level is physically full but the code remains active, inspect the hydraulic oil level switch (sensor) and its wiring harness for damage, corrosion, or an open circuit.

1. 1

   Top Up Fluid

   If the hydraulic oil is genuinely low, add the manufacturer-approved hydraulic/transmission fluid to the correct level on the dipstick or sight glass.

2. 2

   Cycle Power

   After topping up, cycle the tractor's key switch (power down and restart) to see if the code clears.

3. 3

   Test the Sensor

   If the reservoir is full but the code persists, use a multimeter to test the hydraulic oil level switch. The sensor operates by closing the circuit if the level falls too low. If the switch is stuck closed while submerged in oil, it has failed.

4. 4

   Replace the Sensor

   Disconnect the electrical connector from the faulty hydraulic oil level switch. Unthread the old sensor from the reservoir/tank. Install the new sensor (ensure the O-ring or seal is seated properly) and reconnect the wiring harness.

5. 5

   Clear Codes

   Clear the stored diagnostic trouble codes via the CommandCenter™ display or a diagnostic scan tool, then run the machine at operating temperature to verify the repair.