John Deere 1387.01 – PTA: Lube Oil Pressure Sensor, Oil Pressure Too Low

The control software determines that the transmission lube oil pressure has dropped below the minimum safe threshold, forcing limited or no function of the transmission to prevent catastrophic internal damage.

• 6110R
• 6120R
• 6130R
• 6145R
• 6155R
• 6175R
• 6195R
• 6215R
• 6105R
• 6125R
• 6140R
• 6150R
• 6170R
• 6190R
• 6210R
• 6230R
• 6250R
• 6110M
• 6120M
• 6130M
• 6140M
• 6150M
• 6155M
• 6170M
• 6175M
• 6195M
• 7R Series
• 8R/8RT Series
• 9R/9RT Series

1. 1

   Check transmission/hydraulic lube oil level via the dipstick or sight glass

2. 2

   Examine wiring harnesses and connectors associated with the transmission oil pressure sensor for chafing, corrosion, or disconnection

3. 3

   Inspect the lube oil pressure sensor to verify it is not outputting a false low reading

4. 4

   Verify the actual operation of the transmission oil pump using a mechanical pressure gauge to rule out physical pump failure or severe internal leaks (e.g., blown MFWD shaft seal)

1. 1

   Verify Fluid

   Park the tractor on level ground and check the transmission fluid level. Fill with approved John Deere Hy-Gard™ transmission fluid if low. Clear the code and retest.

2. 2

   Inspect Harness

   Locate the transmission lube oil pressure sensor on the transmission housing. Disconnect the pigtail and inspect the pins for moisture, corrosion, or damage. Repair the connector if necessary.

3. 3

   Test/Replace Sensor

   If the wiring is intact and fluid is full, the sensor is the most likely culprit. Replace the transmission oil pressure sensor with a new OEM unit.

4. 4

   Verify Mechanical Pressure

   If replacing the sensor does not clear the 001387.01 code, attach a mechanical hydraulic pressure gauge to the transmission test port.

5. 5

   Internal Repair

   If the mechanical gauge confirms low lube pressure, the tractor will require a transmission teardown to repair or replace the transmission oil pump, or to locate an internal pressure leak (e.g., blown seals).

6. 6

   Recalibrate

   After any major transmission repair or sensor replacement, use a diagnostic tool (like John Deere Service ADVISOR or Jaltest) to clear the codes and perform a transmission calibration.