Case IH F-1073-04 - ECU – ECU: Engine compression brake low side driver circuit short to ground failure

The Engine Control Module (ECM) has detected abnormally low voltage or a short circuit to ground (negative) on the signal circuit for the engine brake actuator/solenoid (specifically solenoid number 2). When this fault is active, the engine brake on the affected cylinders cannot be activated.

• MAGNUM AFS Connect
• 240 Series Axial-Flow Combines
• Magnum AFS Connect Tractors
• Magnum 235
• Magnum 290
• Magnum 315
• Magnum 400
• Steiger Series Tractors

1. 1

   Inspect the wiring harness running from the ECU to the engine compression brake solenoid for chafing, melted insulation, or pinched wires shorting to the engine block or chassis ground.

2. 2

   Disconnect the engine brake solenoid and the ECU connector, then use a multimeter to check for continuity to ground on the low-side driver signal circuit to identify a shorted harness.

3. 3

   Check the internal resistance of the engine compression brake solenoid itself to rule out an internal short within the solenoid coil.

1. 1

   Disconnect Power

   Turn off the machine and disconnect the negative battery terminal to prevent electrical spikes.

2. 2

   Access the Solenoid

   Remove the engine valve cover or access panel as required by your specific engine model to reach the engine compression brake solenoid. (Note: On some Magnum models, a plug and sealing washer may need to be removed from the solenoid housing to correctly access the water pipe location during disassembly).

3. 3

   Repair Wiring (If Applicable)

   If the diagnostic checks revealed a shorted wire, repair the damaged section of the harness using OEM-approved heat-shrink connectors, or replace the affected harness section.

4. 4

   Replace Solenoid (If Applicable)

   If the wiring is intact but the solenoid is internally shorted, unbolt the faulty engine brake solenoid valve and install the replacement part. Torque to OEM specifications.

5. 5

   Reassembly

   Reinstall the valve cover/access panels with new gaskets if required.

6. 6

   Clear Codes

   Reconnect the battery, connect a diagnostic tool, clear the F-1073-04 fault code, and test-run the engine brake to verify the repair.