Case IH NH14091 – ADIC / TCU / ICU: Transmission Output Speed Circuit Issue

The control module has detected a short circuit to the power supply (VCC) or an open circuit in the transmission output speed sensor circuit. This electrical fault prevents the system from receiving a valid signal representing the transmission's output rotational speed, which directly affects the proper functioning of the transmission speed signal and shifting.

• Maxxum 110
• Maxxum 115
• Maxxum 120
• Maxxum 125
• Maxxum 130
• Maxxum 140
• Puma Series
• Farmall 115U Pro EP

1. 1

   Visually inspect the transmission output speed sensor (typically located on the right-hand side of the transmission housing) and its wiring harness for damage or corrosion.

2. 2

   Check for loose connections or corroded pins at the sensor connector (X257), inline harness connectors (X022), and the main controller connector (X093).

3. 3

   Inspect the sensor tip and the corresponding tone/reluctor ring on the transmission shaft for metal shavings, grease, or mud that could disrupt the signal.

4. 4

   Disconnect the sensor and perform basic electrical checks on the harness: verify 12V power on the supply wire (often green) and a proper ground on the ground wire (often black/white).

5. 5

   Test the signal wire running back to the controller for an open circuit or a short to power.

6. 6

   Measure the resistance across the sensor's terminals (for magnetic-type sensors). An open circuit (infinite resistance) indicates a broken internal coil.

7. 7

   If the instrument cluster (ADIC) was recently replaced or an ISO 11783 connector was installed (especially on Maxxum models), check for an ADIC configuration mismatch.

1. 1

   Verify the fault

   Confirm that the fault code 14091 is active. The code may clear itself once the underlying issue is resolved.

2. 2

   Clean sensor and tone ring

   If debris is found during inspection, clean the sensor tip and the transmission tone/reluctor ring to ensure an uninterrupted signal.

3. 3

   Repair wiring and connectors

   Repair or replace any damaged wires, corroded pins, or loose connections found at connectors X257, X022, or X093. Ensure all connectors are clean and securely fastened.

4. 4

   Replace transmission output speed sensor

   If the sensor fails the resistance test (shows infinite resistance) or fails to output a signal despite good wiring and power, replace the transmission output speed sensor.

5. 5

   Reconfigure ADIC (Maxxum models)

   If the fault is caused by an ADIC configuration mismatch, use diagnostic test switch 380000843 to access the 'H menus'. Perform the 'Clear Network Config' procedure to allow the dash to relearn the correct transmission setup.

6. 6

   Replace instrument cluster

   If wiring and the sensor are verified good, and reconfiguration does not resolve the issue (noted specifically on some New Holland TL100A models), the entire dash/instrument cluster may need to be replaced.

7. 7

   Clear codes and verify repair

   Clear the fault codes from the system. Operate the tractor to ensure the code does not return and that the transmission and speedometer are functioning correctly.