Case IH 388 – ENG: Engine Brake driver 1 circuit failure

The Engine Control Module (ECM) has detected a low voltage condition (shorted to ground or open circuit) on the circuit controlling the #1 engine brake solenoid. When this fault is active, the ECM will illuminate the amber CHECK ENGINE lamp, and the engine brake will fail to operate or operate at reduced capacity.

• MX Magnum
• STX Steiger
• Steiger
• Magnum
• Puma
• Axial-Flow 2388
• Axial-Flow 7088

1. 1

   Check Solenoid Resistance: Disconnect the solenoid and measure the coil's resistance. A healthy 12VDC solenoid should read approximately 15.5 ohms (± 15%), and a 24VDC solenoid should read 60 ohms (± 15%). Open circuit or dead short indicates internal failure.

2. 2

   Direct Power Test: Apply a direct power source (minimum 8 volts for a 12V system) to the solenoid terminal and ground the other. Listen and feel for the armature to pull down mechanically to ensure it is not seized.

3. 3

   Harness Continuity & Short Check: Disconnect the harness at the ECM and at the solenoid. Check the wiring for continuity and test for a short to ground, which is the most common cause of this low voltage code.

4. 4

   ECM Pin Inspection: Inspect the ECM connector pins for corrosion, pushed-back pins, or moisture intrusion.

1. 1

   Power Down

   Turn the key switch to the OFF position and disconnect the machine's batteries to prevent electrical arcing.

2. 2

   Access the Solenoid

   Clean the area around the top of the engine and remove the engine valve cover to access the engine brake housing.

3. 3

   Remove the Faulty Solenoid

   Disconnect the electrical lead(s) attached to Engine Brake Solenoid 1. Unthread the solenoid from the engine brake housing.

4. 4

   Install the New Solenoid

   Thread the replacement solenoid into the housing and torque it to the manufacturer's specification (do not over-tighten, as the internal armature can bind).

5. 5

   Reconnect Wiring

   Reattach the electrical leads. Ensure the connections are tight and free of oil saturation.

6. 6

   Reassembly

   Reinstall the valve cover with a new gasket if necessary. Reconnect the batteries.

7. 7

   Validate the Repair

   Turn the key switch to the ON position, start the engine, and let it idle for at least 1 minute. The ECM will run a continuous diagnostic; if the circuit is repaired, the fault code status will change to INACTIVE and the amber warning lamp will turn off. Clear the inactive code using your electronic service tool.