Case IH 521-01 - ITBV – ITBV: Service brake disagreement

The system detects that the operator has pressed the brake pedal, but the tractor's service brake pressure is reading as abnormally low. This means there is a physical or electrical mismatch between the brake pedal's position and the actual hydraulic/pneumatic pressure achieved in the braking circuit.

• MAGNUM AFS Connect
• Magnum 180
• Magnum 200
• Magnum 220
• Magnum 240
• Magnum 250
• Magnum 280
• Magnum 310
• Magnum 340
• Magnum 380
• Puma series
• Farmall series

1. 1

   Inspect the Air Brake Pressure Sensor to verify it is reading correctly and check its wiring harness for chafing, corrosion, or disconnected pins.

2. 2

   Check for leaks in the pneumatic/hydraulic lines, specifically the Trailer Brake Tube running from the ITBV to the Solenoid Valve.

3. 3

   Test the ITBV ECU and Solenoids by checking connections at the Intelligent Trailer Brake Valve ECU and the associated 12V DC solenoid valves for proper voltage and resistance (e.g., 8.5 Ohm specification on the solenoid).

1. 1

   Replace part

   Replace the faulty pressure sensor.

2. 2

   Repair leak

   Repair a leak in the brake lines.

3. 3

   Replace part

   Replace the ITBV valve block/ECU if internal failure has occurred.