Case IH FA5 – Transmission Controller (TCU): Creeper Solenoid Open Circuit Or Short To Ground

The transmission controller has detected a voltage or resistance irregularity in the circuit responsible for engaging the creeper gear solenoid. The controller cannot communicate with or actuate the solenoid because the electrical path is either broken (open circuit) or grounding out improperly (short to ground).

• MXM
• MXM Series
• MXM 120
• MXM 130
• MXM 140
• MXM 155
• MXM 175
• MXM 190
• Maxxum
• Puma

1. 1

   Inspect the chassis wiring harness from the transmission controller to the creeper solenoid for chafed wires, pinched lines, or disconnected plugs

2. 2

   Perform a coil resistance test by disconnecting the electrical connector at the creeper solenoid and measuring resistance across the coil pins (healthy is 6 to 8 Ohms)

3. 3

   Perform a voltage/short test with the ignition ON and the controller disconnected to check the harness pins for a short to positive voltage or a short to ground

1. 1

   Preparation

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

2. 2

   Removal

   Locate the creeper solenoid on the transmission top cover or low-pressure oil distribution manifold. Disconnect the electrical harness plug. Remove the retaining hardware and carefully pull the faulty solenoid valve from the manifold.

3. 3

   Installation

   Lubricate the O-rings on the new creeper solenoid with clean hydraulic oil. Insert the new solenoid into the manifold, secure the retaining hardware, and reconnect the electrical harness.

4. 4

   Transmission Calibration

   With the tractor running, wheels blocked, and parking brake applied, hold the High and Low range buttons simultaneously. 'CAL' will appear in the transmission display. Release the buttons. Set the engine speed to 1200 RPM (± 100 RPM). Follow the on-screen prompts to cycle through and calibrate the clutch packs.