John Deere CCU000090.04 – CCU: PTO Oil Temperature Sensor Circuit Voltage Problem

The Central Control Unit (CCU) has detected an abnormal voltage reading from the PTO oil temperature sensor. This indicates a problem within the electrical circuit of the sensor, which could be caused by a faulty sensor, damaged wiring, or poor connections between the sensor and the control unit.

• 8130
• 8230
• 8330
• 8430
• 8530
• 9230
• 9330
• 9430
• 9530
• 9630

1. 1

   Verify transmission and hydraulic oil levels and condition to ensure they are within specification and rule out genuine overheating.

2. 2

   Visually inspect the wiring harness and connectors associated with the PTO system and transmission for frayed wires, loose connections, corrosion, or damage from debris and heat.

3. 3

   Check for other related fault codes concerning sensor supply voltage or other transmission components that might indicate a broader electrical issue.

4. 4

   Use an infrared thermometer to check the temperature of the PTO/transmission housing to determine if the oil is genuinely overheating or if the sensor is providing a false reading.

1. 1

   Locate the sensor

   Find the PTO oil temperature sensor, which is typically threaded into the transmission or PTO housing.

2. 2

   Test sensor and circuit

   Use a multimeter to test the sensor's resistance and compare it to the manufacturer's specifications. Test the wiring for continuity and check for shorts or open circuits between the sensor and the CCU.

3. 3

   Repair wiring or replace sensor

   If the wiring is damaged, repair or replace it. If the sensor is determined to be faulty, drain the oil to avoid spillage, then remove and replace the sensor.