John Deere 1387.03 – PTA: High Voltage On Transmission Oil Lube Pressure Sensor

This diagnostic trouble code is generated when the control software detects that the voltage at the transmission lube oil pressure sensor is abnormally high. This typically indicates a short to a high voltage source in the sensor circuit, a faulty sensor, or a power supply issue. When this code is active, the transmission may experience limited or no functionality to protect the system from operating with unverified lube pressure.

• 6110R
• 6120R
• 6130R
• 6145R
• 6155R
• 6175R
• 6195R
• 6215R
• 9230
• 9330
• 9430
• 9530
• 9630
• 9360R
• 9410R
• 9460R
• 9510R
• 9560R

1. 1

   Inspect all wiring harnesses and connectors associated with the transmission lube oil pressure sensor for signs of damage, wear, corrosion, or disconnection.

2. 2

   Check the sensor circuit specifically for short circuits to a high voltage source or power.

3. 3

   Ensure the sensor is receiving the correct reference voltage from the PTA module and check for any issues in the power supply that might be causing a voltage spike.

4. 4

   Measure the sensor's voltage output with a multimeter to determine if the sensor is internally shorted and producing abnormally high voltage readings despite normal wiring.

1. 1

   Relieve Pressure

   Relieve hydraulic pressure by stopping the engine and operating all hydraulic control valves before disconnecting any lines or sensors.

2. 2

   Locate the Sensor

   Locate the Transmission Lube Oil Pressure Sensor on the transmission control valve housing.

3. 3

   Disconnect Electricals

   Carefully unplug the wiring harness connector from the sensor.

4. 4

   Remove the Sensor

   Remove the lube pressure sensor. (Note: On some 9-series models, a JDG669 Box End Adapter or similar specialty tool may be required for clearance).

5. 5

   Install the New Sensor

   Thread the new sensor into the housing. Tighten to the specified torque (refer to the specific machine's technical manual, as over-tightening can damage the valve housing).

6. 6

   Reassembly

   Reconnect the electrical harness.

7. 7

   Test

   Start the tractor, check for leaks around the new sensor, and verify that the PTA 001387.03 code can be cleared and does not return.