Case IH 139 – TRANS: Front Suspension lower lock solenoid circuit shorted or open circuit

This code indicates a critical electrical failure in the circuit controlling the front suspension's lower lock solenoid. The controller has detected that the circuit is either open (e.g., a broken wire, disconnected plug, or burnt-out solenoid coil) or shorted (e.g., wires touching each other, shorted to ground, or an internally shorted solenoid coil).

• MX Magnum
• MX Series
• TG Series
• Magnum Series
• Steiger
• TG210
• TG230
• TG255
• TG285
• TM175

1. 1

   Visually inspect the front suspension control valve block, wiring harness, and connector going to the lower lock solenoid for physical damage, frayed wires, or severe corrosion.

2. 2

   Perform a solenoid coil resistance test by disconnecting the electrical connector and measuring resistance across the pins (OL indicates an open circuit, near 0 ohms indicates a short).

3. 3

   Perform a harness continuity test from the solenoid connector back to the Transmission Control Module (TRANS) to check for shorts to ground or power.

1. 1

   Preparation

   Park the tractor on a hard, level surface. Lower all implements to the ground, engage the parking brake, turn off the engine, and remove the key. Note: Ensure the front suspension is fully depressurized or mechanically supported if you are removing the hydraulic valve cartridge.

2. 2

   Disconnect

   Disconnect the negative battery cable to prevent electrical spikes.

3. 3

   Access the Solenoid

   Locate the lower lock solenoid on the front suspension manifold block. Disconnect the wiring harness connector.

4. 4

   Harness Repair

   If the wiring was pinched or broken, splice in a new section of wire using weather-sealed heat-shrink connectors, or replace the damaged pigtail connector.

5. 5

   Remove the Solenoid

   Remove the retaining nut or clip at the end of the solenoid stem. Slide the faulty electromagnetic coil off the hydraulic valve cartridge.

6. 6

   Install the New Solenoid

   Slide the new solenoid coil over the valve stem and secure it with the retaining nut. Do not overtighten, as this can crack the plastic casing of the coil.

7. 7

   Reconnect

   Plug the electrical connector back into the solenoid. Reconnect the battery.

8. 8

   Clear Codes and Calibrate

   Turn the key on and use the tractor's Armrest display or an Electronic Service Tool (EST) to clear the TRANS 139 fault code. You may need to navigate to the 'FSUS CAL' (Front Suspension Calibration) menu to recalibrate the suspension travel range if the system was locked out.