John Deere 524161.19 – PTA / TCU: Incorrect CAN BUS Message, Desired Acceleration from UIC

The User Interface Controller (UIC) is unable to determine the desired acceleration value (DTOA / DTOAPR) from the operator's inputs, particularly when changing the direction of travel. Because the UIC cannot calculate the actual acceleration demand, it broadcasts a default replacement value over the CAN BUS, which triggers this fault code in the transmission system.

• 6110R
• 6120R
• 6130R
• 6145R
• 6155R
• 6175R
• 6195R
• 6215R
• 6230
• 6330
• 6430
• 6020
• 6120
• 6220
• 6320
• 6420
• 6520
• 6620
• 6820
• 6920
• 6920S
• 7010 Series
• 7030 Series

1. 1

   Check for accompanying codes in the UIC or EPC modules (such as EPC 000091.04 or UIC 305005.02) which directly point to the pedal sensor or controller.

2. 2

   Inspect the wiring harness and connections between the accelerator pedal potentiometer (Sensor B79) and the UIC for damaged insulation, exposed wires causing a short to ground, or open circuits.

3. 3

   Test the voltage sweep of the accelerator pedal potentiometer using a multimeter or diagnostic tool to ensure it provides smooth, accurate voltage readings without dropping out.

4. 4

   Verify CAN BUS communication lines between the UIC and the PTA/TCU for secure, clean terminal connections and proper resistance.

1. 1

   Disconnect Power

   Disconnect the tractor's battery to prevent electrical damage while working with the electronic control modules.

2. 2

   Access the Sensor

   Locate the accelerator pedal potentiometer (B79) under the operator platform/cab floor.

3. 3

   Clean and Inspect

   Disconnect the sensor harness. Inspect the connector pins for moisture, dirt, or corrosion. Clean the terminals with contact cleaner and ensure a tight fit.

4. 4

   Replace the Sensor

   If the wiring is intact but the potentiometer failed the voltage sweep test, unbolt the sensor from the pedal linkage and install a direct replacement.

5. 5

   Inspect the UIC

   If the pedal sensor and wiring test perfectly, the fault may lie within the UIC itself. Check the UIC connections. If the controller has internal hardware faults, the UIC module must be repaired or replaced.

6. 6

   Relearn and Test

   Reconnect the battery. Clear the stored fault codes using a diagnostic tool. Start the tractor and test the throttle response, specifically checking acceleration while changing the direction of travel to ensure the CAN BUS is receiving the correct DTOA values.