Case IH 520711-13 - ITBV – Trailer Brake Control Module / Intelligent Trailer Brake Valve (iTBV) ECU: Tractor service brake pressure sensor fault

The service brake pressure sensor signal is out of its calibrated range, or it has failed a plausibility check (e.g., the brake pedal switch indicates it is released, but the pressure sensor shows high demand pressure).

• MAGNUM AFS Connect
• Case IH Magnum 180
• Case IH Magnum 200
• Case IH Magnum 220
• Case IH Magnum 240
• Case IH Magnum 250
• Case IH Magnum 280
• Case IH Magnum 310
• Case IH Magnum 340
• Case IH Magnum 380

1. 1

   Perform a plausibility check by verifying the physical state of the brake pedal against the sensor readings (e.g., ensure the brake switch does not read 'low' while demand pressure reads 'high')

2. 2

   Inspect the service brake pressure sensor circuit for a short to 12 volts, a short to ground, or an open circuit/disconnected line

3. 3

   Monitor live data in the tractor's diagnostic screen (DIAG -> BRAKES -> SERVICE PRESS SW) to see if the sensor is stuck or fluctuating erratically

4. 4

   Verify the software version of the Trailer Brake Control (iTBV) module is up to date (e.g., software part number 51595354 for some Magnum models)

1. 1

   Access the Sensor

   Locate the service brake pressure sensor and the ITBV pneumatic valve assembly (often routed near the transmission filter or air reservoir depending on the specific chassis).

2. 2

   Inspect Wiring

   Visually inspect the wiring harness and electrical connectors leading to the sensor. Look for rubbed wires, corrosion in the connector cap, or a failed internal regulator.

3. 3

   Test the Sensor

   If the wiring is intact and no shorts to 12V are found, the sensor itself is likely faulty or stuck.

4. 4

   Replace Component

   Replace the faulty service brake pressure sensor or the integrated ITBV pneumatic valve if the sensor is not serviced separately.

5. 5

   Recalibrate

   Perform a brake system/sensor calibration using the Electronic Service Tool (EST) or the tractor's onboard diagnostic interface after replacing the part.

6. 6

   Clear Codes

   Clear the fault code from the ITBV ECU and test drive the tractor to ensure the trailer brake system engages properly without throwing a plausibility error.