John Deere 177 – CCU, TCU, PTP / PTA, EPC, BIF: Transmission Oil Temperature Very High

The transmission oil temperature has exceeded a critical operational threshold (typically above 100°C or 106°C).

• 6110M
• 6120M
• 6130M
• 6145M
• 6155M
• 6175M
• 6195M
• 6110R
• 6120R
• 6130R
• 6145R
• 6155R
• 6175R
• 6195R
• 6215R
• 6090MC
• 6100MC
• 6110MC
• 6090RC
• 6100RC
• 6110RC
• 7220
• 7320
• 7420
• 7520
• 210L EP
• 450K
• 550K
• 750J
• 850J
• 850JR
• X304

1. 1

   Halt operation immediately, reduce the load, and allow the transmission oil to cool

2. 2

   Inspect the transmission oil cooler for blockages caused by dust, chaff, or debris

3. 3

   Inspect the transmission oil cooler lines for pinched hoses or physical restrictions

4. 4

   Check the transmission/hydraulic oil level, as low fluid can cause rapid overheating

5. 5

   Test the transmission oil temperature sensor (B60) and inspect its wiring harness (lead 6002) for shorts or opens

1. 1

   Cool down machine

   Safely park the machine, shift to neutral/park, and let the engine idle to allow the transmission system to cool down.

2. 2

   Clean the cooler

   If the transmission oil cooler is plugged, clean the fins thoroughly using compressed air or water.

3. 3

   Correct fluid level

   Check the transmission dipstick or sight glass. If the oil level is low, top it off with the specified John Deere transmission/hydraulic fluid.

4. 4

   Clear line restrictions

   Reroute or replace any pinched or damaged oil cooler lines.

5. 5

   Test or replace sensor

   If the cooling system is clean, lines are clear, and fluid is full but the code persists, unplug the sensor and test its resistance. Replace the transmission oil temperature sensor if it is faulty or providing out-of-range voltage.

6. 6

   Clear and test

   Clear the fault code from the CCU/TCU and operate the machine under a normal load to verify the temperature remains in the safe operating range.