Fendt 04.1.58 – Basic Control Unit ECU (A050) or Enhanced Control Unit (A002): Transmission slip monitor (Transmission hydraulics)

Transmission output speed deviates by more than 30% from the setpoint value (a mismatch in the ideal gear ratio vs. actual gear ratio comparison). The Tractor Management System (TMS) is automatically switched off to protect the transmission.

• 309 Vario COM III
• 310 Vario COM III
• 311 Vario COM III
• 312 Vario COM III
• 309 Vario
• 310 Vario
• 311 Vario
• 312 Vario
• 409 Vario
• 410 Vario
• 411 Vario
• 412 Vario
• 413 Vario
• 414 Vario
• 415 Vario
• 711 Vario
• 712 Vario
• 714 Vario
• 715 Vario
• 716 Vario
• 717 Vario
• 718 Vario
• 815 Vario
• 817 Vario
• 818 Vario
• 820 Vario
• 916 Vario
• 920 Vario
• 922 Vario
• 924 Vario
• 926 Vario
• 927 Vario
• 930 Vario
• 933 Vario
• 936 Vario

1. 1

   Determine if the tractor is operating in extremely low temperatures, as cold, thick oil can trigger a false slip monitor fault

2. 2

   Depress the clutch pedal or activate the turbo-clutch (TK) function; if the fault deactivates, the issue is actively being monitored by the system's ratio comparison logic

3. 3

   Check the clutch on the transmission actuator unit (A009) for faults

4. 4

   Verify the signals from the Hall sensors on the hydrostatic collecting shaft (B014) and the bevel pinion (B015)

5. 5

   Check the transmission oil temperature via the thermo switch (B009) and the high-pressure circuit oil pressure via the high-pressure sensor (B008)

1. 1

   Warm-Up / Fluid Check

   If operating in freezing conditions, allow the transmission fluid to reach operating temperature. Check the transmission oil level and condition. If the oil is burnt or degraded due to overheating, drain and refill the system.

2. 2

   Sensor Replacement

   If diagnostics point to a missing or erratic speed signal, locate the B014 (collecting shaft) or B015 (bevel pinion) Hall sensors on the transmission block. Disconnect the wiring harness, remove the faulty sensor, and install a replacement.

3. 3

   Actuator Unit Repair/Replacement

   If the sensors are functioning correctly, the fault likely lies within the A009 Actuator Unit or its internal clutch. Access the actuator unit, check the mechanical connection to the actuator shaft, and replace the A009 unit if the internal clutch or incremental encoder has failed.

4. 4

   Calibration

   After replacing the sensors or the actuator unit, perform a full transmission calibration (Note: calibration is blocked while the 04.1.58 fault is actively present).

5. 5

   Clear Codes

   Use the FENDIAS diagnostic system or the tractor's Variotronic terminal to clear the stored fault codes.