John Deere 191.11 – PTA / TCU: Transmission Output Speed Does Not Correspond to Wheel Speed

The control software has detected a frequency discrepancy between the signal coming from the transmission output speed sensor (B63) and the amplified signal from the wheel speed sensor (B84), causing the tractor to enter a protective mode with limited or no transmission function.

• 6110R
• 6120R
• 6130R
• 6145R
• 6155R
• 6175R
• 6195R
• 6215R
• 6230
• 6330
• 6430
• 6120
• 6220
• 6320
• 6420
• 6520
• 6820
• 6920
• 6010
• 6110
• 6210
• 6310
• 6410
• 6510
• 6610
• 6810
• 6910

1. 1

   Compare Sensor Signals: Use a John Deere diagnostic tool to monitor the live frequency outputs of both the B63 (Transmission Output) and B84 (Wheel Speed) sensors while moving. Identify which sensor is dropping the signal or providing erratic readings.

2. 2

   Inspect Wiring and Connectors: Check the wiring harnesses for both sensors. Look for chafed wires, shorts to ground, or open circuits. Ensure the connectors are tight and free of moisture or corrosion.

3. 3

   Check Sensor Alignment: Ensure both sensors are correctly seated, aligned, and installed to the proper depth. A loose sensor will fail to read the reluctor ring properly.

4. 4

   Verify PLC/CAN BUS Communication: The B84 wheel speed sensor signal is often processed by the PLC and sent to the TCU via CAN BUS. Check for any priority codes logged in the PLC (such as PLC 328012.31 or TCU 524109.10) which would indicate a primary failure of the B84 circuit.

1. 1

   Locate the Sensors

   Identify the B63 Transmission Output Speed Sensor (typically located on the transmission housing) and the B84 Wheel Speed Sensor.

2. 2

   Harness Repair (If Applicable)

   If the diagnostic checks revealed a short or break in the wiring harness, splice and heat-shrink the damaged wires, or replace the affected harness section.

3. 3

   Remove the Faulty Sensor

   If wiring is intact but a sensor failed the frequency/voltage test, disconnect the electrical connector from the faulty sensor. Unbolt and carefully remove the sensor from its mounting port.

4. 4

   Install the New Sensor

   Lubricate the O-ring on the new sensor (if applicable) with clean hydraulic/transmission fluid. Insert the sensor, secure the mounting bolt to OEM torque specs, and reconnect the wiring harness.

5. 5

   Calibrate and Test

   Clear the 000191.11 fault code from the PTA/TCU. Test drive the tractor under normal conditions to ensure the transmission output speed and wheel speed synchronize correctly and the transmission shifts out of protective mode.