Case IH FAF – Transmission Controller / TCU / EDC: PTO Lube Solenoid Open Circuit Or Short To Ground

The PTO lube solenoid is experiencing an open circuit, short to ground, or under voltage condition.

• MXM
• MXM 120
• MXM 130
• MXM 140
• MXM 155
• MXM 175
• MXM 190
• Magnum 295
• Magnum 340

1. 1

   Perform a resistance test on the PTO lube solenoid with the ignition OFF (should read between 8 and 11 Ohms across terminals 1 and 2).

2. 2

   If the solenoid resistance is okay, check the wiring harness between the TCU and the solenoid for an open circuit or short to ground.

3. 3

   Verify +12 volts and continuity at the TCU connector with the ignition switch ON.

4. 4

   Ensure there is no mechanical binding preventing the solenoid from opening and closing during feathering operation.

1. 1

   Preparation

   Park the tractor on level ground, place all shift levers in neutral, apply the parking brake, and block the wheels.

2. 2

   Wiring Repair

   If the diagnostic checks revealed a wiring issue (short to ground or open circuit), trace the harness from the TCU to the PTO lube solenoid. Repair any broken wires, chafed insulation, or corroded connector pins.

3. 3

   Solenoid Replacement

   If the solenoid failed the resistance test, remove the retaining cover/screws holding the PTO lube solenoid to the transmission/PTO valve block and extract the faulty solenoid. Install the new OEM solenoid and reconnect the wiring harness.

4. 4

   Transmission Calibration

   Ensure transmission oil is between 20°C and 50°C. Apply the parking brake, turn off the AC, and deselect all electrical and hydraulic services. Press and hold the High and Low range buttons and start the engine. Release the buttons when ''CAL'' appears in the transmission display. Set engine speed to 1200 ERPM and follow the on-screen prompts to complete the clutch and solenoid calibration until ''END'' is displayed.