Case IH 5913-15 - DEC – Transmission Control Unit (TCU): Transmission oil temperature sump data valid, above normal range - least severe.

This is an early-warning (pending) code indicating that the transmission oil temperature sensor is reading a temperature that is higher than the normal operating range, but it has only reached the "least severe" warning threshold. It means the transmission fluid is getting hot, which is common during heavy draft work in warm conditions, but it has not yet reached a critical failure temperature. If ignored, sustained high temperatures can damage the transmission's hydrostatic unit or clutch packs.

• MAGNUM AFS Connect
• Magnum Series (180, 190, 200, 210, 225, 235, 240, 340)
• Puma Series (130, 145, 150, 165, 180, 195, 210, 220, 240)
• Maxxum Series (110, 115, 125, 130, 140, 150, 5120-5250)
• Steiger Series

1. 1

   Check the transmission oil cooler and radiator matrix for blockages caused by dust, chaff, or mud. Clean them thoroughly.

2. 2

   Verify the transmission fluid (Hy-Tran) is at the correct level. Low fluid volume causes rapid overheating.

3. 3

   Check for a clogged transmission filter or a blocked suction strainer (located behind the plate near the sensor on some models) that can restrict flow and cause heat buildup.

4. 4

   Inspect the wiring harness and the connector at the sensor for corrosion, moisture, or a short to ground/power, which can cause the ECU to read a falsely high voltage/temperature.

1. 1

   Cool Down

   Park the tractor on a level surface, engage the parking brake, and allow the transmission to cool completely to avoid burns from hot hydraulic fluid.

2. 2

   Locate the Sensor

   The transmission oil temperature sensor is typically located on the lower right side of the transmission case, near the sump or valve body.

3. 3

   Clean the Area

   Wipe away all dirt and grease from around the sensor to prevent contamination from entering the transmission case.

4. 4

   Disconnect

   Unplug the electrical bayonet connector from the sensor.

5. 5

   Remove the Sensor

   Place a clean drain pan under the sensor location, as some fluid will escape. Unscrew the old sensor using the appropriate wrench. (Note: On some older Maxxum models, the sensor is housed behind a plate that requires draining the oil to access the internal strainer, but the sensor itself threads in).

6. 6

   Install the New Sensor

   Apply a dab of hydraulic-safe thread sealant to the threads of the new sensor (if it does not have a pre-applied sealant or an O-ring). Thread it into the transmission case and tighten to OEM torque specs.

7. 7

   Reconnect

   Plug the wiring harness back into the new sensor.

8. 8

   Top Off Fluid

   Check the transmission dipstick/sight glass and top off the fluid with Case IH Hy-Tran Ultraction to replace any oil lost during the swap.

9. 9

   Test

   Start the tractor, check for leaks around the sensor threads, and verify that the 5913-15 fault code has cleared from the cab display.