Case IH 518584-05 - UCM – UCM: Brake assisted steering cut off valve solenoid current low / Brake assisted steering pressure mismatch

This fault code indicates a problem with the electrical circuit controlling the Brake Assisted Steering (BAS) cut-off valve solenoid. The system detects that the electrical current flowing to the solenoid is below the minimum operational threshold (an open circuit, high resistance, or a failed solenoid coil). The BAS system automatically applies the inside rear brake during headland turns to reduce the turning radius; when this code is active, the automated braking assist will be disabled.

• MAGNUM AFS Connect
• Magnum 280
• Magnum 310
• Magnum 340
• Magnum 380
• Magnum 400
• Steiger 370
• Steiger 420
• Steiger 470
• Steiger 500
• Steiger 540
• Steiger 580
• Steiger 620

1. 1

   Verify the UCM is receiving proper voltage. Check for accompanying UCM power supply codes (e.g., 1903, 1904, 1905) which can cause false solenoid codes.

2. 2

   Inspect the specific 'Wire Harness, Brake-Assisted Steering' for chafing, pinch points, or rodent damage between the UCM and the rear differential valve block.

3. 3

   Disconnect the BAS cut-off valve solenoid and measure the resistance across the coil pins with a multimeter. A healthy 12V DC PWM solenoid in this circuit should measure approximately 7.3 Ohms (or 8.5 Ohms depending on the exact valve revision). If it reads open (infinite resistance) or significantly out of spec, the coil is dead.

4. 4

   Check the solenoid connector for water ingress, corrosion, or pushed-back pins.

1. 1

   Locate the Valve Block

   Locate the PTO / Differential / Brake Assisted Steering valve block, which is mounted on the top/rear of the transmission and differential housing.

2. 2

   Clean the Area

   Thoroughly clean the area around the valve block to prevent dirt from entering the hydraulic system.

3. 3

   Remove the Solenoid

   Disconnect the electrical harness from the BAS LH Solenoid. Remove the solenoid retaining cover/nut.

4. 4

   Extract the Coil

   Slide the faulty electric actuator solenoid (PWM coil) off the valve cartridge stem. (If the cartridge itself is leaking or stuck, the entire valve may need to be unthreaded and replaced, but a "current low" code usually only requires replacing the electrical coil).

5. 5

   Install the New Part

   Slide the new solenoid coil onto the stem, secure the retaining nut/cover, and plug in the electrical connector.

6. 6

   Clear and Calibrate

   Turn the key on, use the AFS Pro 1200 display or the EST (Electronic Service Tool) to clear the UCM fault codes, and perform a test drive to verify the BAS system engages on tight turns without throwing the code.