Case IH 520525-06 - ITBV – ITBV: Inlet valve current high

The system has detected that the electrical current draw for the inlet solenoid valve is above normal, indicating a short circuit to ground in the wiring harness or an internal short circuit within the solenoid coil itself.

• MAGNUM AFS Connect
• AFS Connect Magnum 180
• AFS Connect Magnum 200
• AFS Connect Magnum 220
• AFS Connect Magnum 240
• AFS Connect Magnum 250
• AFS Connect Magnum 280
• AFS Connect Magnum 310
• AFS Connect Magnum 340
• AFS Connect Magnum 380
• Farmall 115U Efficient Power

1. 1

   Inspect the wiring harness running from the ITBV controller to the inlet solenoid valve for chafed insulation, pinched wires, or melted areas that could cause a short to ground.

2. 2

   Disconnect the connector at the inlet solenoid valve and use a multimeter to measure the resistance across the coil pins. A reading of 0 ohms confirms an internal short in the actuator.

3. 3

   Inspect the ITBV module and valve connectors for water ingress, corrosion, or bent pins that could bridge the circuits.

4. 4

   Check the ITBV power supply fuses (e.g., F-030 for ITBV UNSW B+ or F-601/F-602) to see if the high-current short caused a fuse to blow.

1. 1

   Power Down

   Turn off the tractor, remove the key, and disconnect the battery to prevent further electrical damage.

2. 2

   Locate the ITBV

   Locate the Intelligent Trailer Brake Valve assembly, typically mounted near the rear pneumatic brake lines and air tanks.

3. 3

   Isolate the Fault

   Disconnect the electrical connector at the inlet solenoid valve. Test the harness side for continuity to ground.

4. 4

   Repair Wiring or Replace Valve

   If the harness is shorted to ground, repair the damaged section of the wire or replace the affected sub-harness. If the solenoid coil is internally shorted, replace the ITBV solenoid valve. If the solenoid cannot be serviced separately on your specific valve block, replace the complete ITBV assembly.

5. 5

   Reassembly

   Reconnect the wiring harness and restore battery power.

6. 6

   Clear Codes & Test

   Use the Case IH Electronic Service Tool (EST) to clear the fault code. Perform a functional test of the pneumatic trailer brakes to ensure the code does not return and the brakes apply/release correctly.