Case IH 11091 – Transmission Controller (TCU) or ADIC (Instrument Cluster / Armrest Controller): Transmission output speed sensor short to Vcc (12V+) or open circuit

The control module is detecting a broken connection (open circuit) to the transmission output speed sensor (road speed sensor) or the sensor's signal wire is shorted to a positive voltage source.

• Puma 115
• Puma 125
• Puma 140
• Puma 150
• Puma 165
• Puma 180
• Puma 200
• Puma 210
• Puma 225
• Puma 240
• Puma CVT
• MXU100
• MXU110
• MXU115
• MXU125
• MXU135
• Maxxum 100
• Maxxum 110
• Maxxum 115
• Maxxum 125
• Maxxum 135
• Maxxum 140
• Maxxum 150
• Magnum 180
• Magnum 200
• Magnum 225
• Magnum 240
• Magnum 250
• Magnum 280
• Magnum 310
• Magnum 340
• Magnum 380
• Farmall 55C
• Farmall 60A
• Farmall 70A
• Farmall 90C
• Farmall 120C
• Optum 250 CVX
• Optum 270 CVX
• Optum 300 CVX

1. 1

   Check for Recent Panel Replacement (Known Glitch): If the ADIC instrument panel was recently replaced on a 16x16 transmission tractor, code 14091 will trigger erroneously because new replacement panels are configured for a 24x24 transmission by default. Reconfigure to the correct tractor build and recalibrate.

2. 2

   Wiring and Connector Inspection: Inspect the transmission output speed sensor wiring harness and connector (e.g., connector X555) for corrosion, backed-out pins, or physical damage that would cause an open circuit or a short to 12V+.

3. 3

   Sensor Signal Comparison: Use a multimeter to verify if the sensor is actually outputting a pulse frequency signal or if the circuit is dead by comparing the signals of the two output speed sensors (TOS #1 and TOS #2).

1. 1

   Verify Configuration

   If the tractor recently had software updates or a dash replacement, configure the panel to the correct transmission build and recalibrate all functions. If the code persists, proceed to hardware replacement.

2. 2

   Locate the Sensor

   Locate the transmission output speed sensor on the rear axle/transmission housing.

3. 3

   Disconnect the Harness

   Unplug the weather-pack connector from the sensor.

4. 4

   Remove the Sensor

   Unbolt and remove the old sensor from the transmission housing. Be prepared for a small amount of transmission oil to weep from the port.

5. 5

   Install the New Sensor

   Ensure the new sensor has a fresh, heavy-duty synthetic rubber O-ring installed to prevent leaks. Seat the sensor into the transmission casing port and tighten the mounting bolt.

6. 6

   Reconnect and Clear

   Reconnect the wiring harness, clear the fault codes from the ADIC/TCU, and test drive the tractor to ensure the speedometer registers correctly and the transmission shifts without dropping gears.