Case IH 163 – TMF (Tractor Multi-Function / Transmission Management Function) Controller: PTO Shaft rotation is detected when the PTO clutch is OFF

The control system is reading rotational speed from the Power Take-Off (PTO) shaft when the PTO switch is disengaged and the shaft should be completely stationary.

• Magnum
• MX Magnum
• Magnum series
• Puma series
• Maxxum series
• Steiger

1. 1

   Disconnect any attached implement to ensure the implement's inertia is not back-driving the PTO shaft.

2. 2

   Warm up the tractor, shut off the engine, and attempt to turn the PTO stub shaft by hand. If it turns freely, rotation may be caused by cold hydraulic oil drag. If it does not turn or spins with force while running, the PTO brake has likely failed.

3. 3

   Inspect the PTO speed sensor and its wiring harness for shorts, breaks, or corrosion, which can send a false rotation signal.

4. 4

   Verify that the PTO brake solenoid is functioning and that the clutch PWM valve is not stuck open, causing the clutch to drag and overpower the brake.

1. 1

   Drain fluid

   Drain the hydraulic/transmission fluid from the rear frame.

2. 2

   Disconnect harness

   Disconnect the electrical harness from the PTO speed sensor and the PTO control solenoids.

3. 3

   Disconnect hydraulic lines

   Disconnect any external hydraulic lines routed to the PTO housing.

4. 4

   Remove PTO housing

   Unbolt and carefully remove the rear PTO housing/cover from the rear of the transmission.

5. 5

   Disassemble and inspect

   Disassemble the PTO clutch carrier drum. Inspect the clutch friction plates and the PTO brake components. Depending on the tractor model, the brake will either be a brake band (common on Maxxum/Puma) or a multi-disc friction brake pack (common on Magnum).

6. 6

   Replace brake components

   Replace the worn PTO brake band or brake friction discs and separator plates.

7. 7

   Replace seal rings

   Replace the Teflon seal rings on the clutch drum if they are worn, warming them in hot water to stretch them gently over the drum.

8. 8

   Replace sensor

   If diagnostics pointed to a sensor failure, replace the PTO speed sensor.

9. 9

   Reassemble and refill

   Reassemble the PTO housing with new gaskets/seals, bolt it back to the rear frame, and refill the transmission fluid.

10. 10

    Perform calibration

    Connect a diagnostic tool to the CAN bus and perform a PTO calibration procedure to ensure the TMF controller properly synchronizes the clutch and brake modulation valves.