Case IH P03 – Electronic Management Unit (EMU): Rear PTO Brake Output Open Circuit

The electronic controller has detected a break in the electrical circuit (an open circuit) leading to the rear Power Take-Off (PTO) brake solenoid, preventing the system from engaging or disengaging the PTO brake properly.

• MXM
• Maxxum / MXM Series (MXM 120, 130, 140, 155, 175, 190)
• Puma Series (140, 165, 180, 195, 210, 225)
• Magnum Series
• Steiger Series
• CVX Series (CVX 170)
• CS 150

1. 1

   Inspect the main connector for the Rear PTO Brake Solenoid (C033, X277, or X278) to ensure it is connected correctly and securely.

2. 2

   Disconnect the connector from the solenoid and check the resistance across the solenoid terminals using a multi-meter. An infinite resistance reading indicates an internal open circuit.

3. 3

   Check the wiring harness at the connector and trace it back to the Electronic Management Unit (EMU) for any breaks, chafing, or disconnected wires.

4. 4

   If a short circuit is indicated during testing rather than an open circuit, substitute the Electronic Management Unit to verify if the module has failed.

1. 1

   Clean and refit connector

   If the connector was simply loose, clean the contacts and refit the connector correctly.

2. 2

   Repair wiring harness

   If the wiring harness is damaged, repair the broken wire(s) between the EMU and the PTO brake solenoid.

3. 3

   Replace solenoid

   If the multi-meter test confirms the solenoid has an open circuit, remove and replace the Rear PTO Brake Solenoid.

4. 4

   Clear codes and test

   After replacing the faulty component or repairing the wire, clear the fault codes from the Electronic Management Unit and test the rear PTO functions multiple times to ensure the code does not return.