Valtra A311 – A1A3: Gearbox Oil Temp Sensor Over 150°C

The system indicates that the gearbox oil temperature value from sensor B14 is impossibly high, exceeding +150°C. This suggests a fault with the sensor itself or its wiring, rather than an actual overheating of the gearbox oil. If this sensor is faulty, it can lead to malfunctions in the transmission's multi-disc clutches, such as delays or jerking, and will disable the shuttle automatics.

• 6000 series
• A series
• N series
• T series
• S series

1. 1

   Use the tractor's test mode (FII) to check the sensor's reading and compare the displayed temperature with the actual oil temperature to verify accuracy

2. 2

   Inspect the wiring and connectors for the sensor (connectors X13, X19) for any signs of damage, corrosion, or loose connections

3. 3

   Measure the resistance of the sensor from connector X13 at pins 10 and 6. Expected values: 1600 Ω at 0°C, 2000 Ω at +25°C, 3300 Ω at +100°C

1. 1

   Locate the sensor

   Locate the gearbox oil temperature sensor B14 on the servo valve block on the left-hand side of the gearbox.

2. 2

   Perform diagnostics

   Carry out the diagnostic checks listed above to confirm whether the sensor or the wiring is the source of the fault.

3. 3

   Repair wiring

   If the wiring or connectors (X13, X19) are found to be damaged or corroded during inspection, repair or replace the faulty section.

4. 4

   Replace the sensor

   If the resistance measurements are out of specification or the test mode confirms the sensor is faulty, replace sensor B14.

5. 5

   Final system check

   Clear the fault codes and carry out all points in the test mode to ensure the tractor is functioning correctly. If the control unit or its programs were changed, re-apply necessary settings.