Case IH F-1072-14 - ECU – Engine Control Unit (ECU): Engine compression brake high side driver circuit short to battery and low side driver circuit short to ground failure

The control module has detected a simultaneous electrical fault in the circuit that operates the engine compression brake (often referred to as a Jake brake). Specifically, the high side (power supply) of the circuit is shorted to the battery voltage, and the low side (ground/control) of the circuit is shorted directly to the ground, preventing the compression brake actuator from functioning correctly.

• MAGNUM AFS Connect
• Magnum AFS Connect Series Tractors (e.g., Magnum 250, 280, 340, 380, 400 Tier 3 and Tier 4 models)
• Steiger AFS Connect Series Tractors (e.g., Steiger 420, 580)
• 240 Series Axial-Flow Combines
• Austoft 9900 Sugar Cane Harvesters

1. 1

   Visually inspect the wiring harness running from the ECU to the engine compression brake solenoid/actuator for chafing, melted insulation, or pinched wires.

2. 2

   Disconnect the compression brake actuator and use a multimeter to check the high side driver pin at the connector for an unwanted short to battery voltage, and the low side driver pin for an unwanted short to ground.

3. 3

   Test the engine compression brake relay and power stage to ensure the relay is not stuck closed or internally shorted.

4. 4

   Test the compression brake solenoid itself for an internal short circuit that could be bridging the high and low sides.

1. 1

   Power Down

   Turn off the machine, lower all implements, and disconnect the negative battery terminal to prevent electrical spikes during repair.

2. 2

   Access the Actuator

   Locate the engine compression brake solenoid/actuator, typically located under the engine valve cover or on the cylinder head depending on the specific FPT engine model.

3. 3

   Repair Wiring (If Applicable)

   If the diagnostic checks revealed a short in the wiring harness (e.g., wires rubbed bare against the engine block), cut out the damaged section and splice in a new wiring pigtail using weather-sealed connectors.

4. 4

   Replace Relay (If Applicable)

   If the wiring is intact but the compression brake relay is faulty, pull the old relay from the power distribution block and install a new OEM relay.

5. 5

   Replace the Actuator (If Applicable)

   If the solenoid/actuator failed the resistance test (internal short), remove the retaining hardware, extract the faulty actuator, and install a new replacement unit. Torque the mounting bolts to OEM specifications.

6. 6

   Reassemble and Clear Codes

   Reconnect the wiring harness and the battery. Connect a diagnostic tool (such as the Case IH EST) to the machine, clear the F-1072-14 inactive code from the ECU, and run the engine to verify that the compression brake operates normally without triggering a check engine light.