Case IH 19431 – Engine Control Module (ECM) / Engine Control Unit (ECU): Engine compression brake high side driver circuit short to battery and low side driver circuit short to ground failure

This fault code indicates a severe dual electrical failure in the engine compression brake control circuit: the high side of the circuit is receiving unintended battery voltage (short to battery), and the low side of the circuit is improperly grounded (short to ground). This prevents the Engine Control Module from regulating the engine brake, disabling the system.

• Tier 4b
• Case IH 240 Series Axial-Flow Combines
• Case IH Magnum Tractors
• Case IH Steiger / Quadtrac Tractors
• Case IH / STM N Series Loaders

1. 1

   Visually inspect the engine wiring harness routing from the ECM to the engine compression brake solenoid valve. Look for chafed insulation, melted wires, or pinch points against the engine block that could cause a short to ground or battery.

2. 2

   Use a breakout harness when testing FPT engine harnesses to prevent damage to the ECM pins.

3. 3

   Disconnect the electrical connector at the engine compression brake solenoid. Test the harness side of the connector with a multimeter. Check the high side pin for voltage (with the circuit uncommanded) and the low side pin for continuity to ground. If the shorts are present while disconnected, the wiring harness is at fault.

4. 4

   If the harness tests fine, measure the internal resistance of the engine compression brake solenoid valve. An internal failure of the solenoid coil can bridge the circuits, causing the ECM to read the short.

5. 5

   Inspect the ECM connectors for water intrusion, corrosion, or bent pins, which can bridge circuits and cause false short-circuit readings.

1. 1

   Disconnect Power

   Disconnect the machine's battery to prevent electrical spikes during the repair.

2. 2

   Access the Component

   Locate the engine compression brake solenoid valve, typically situated on the upper engine cylinder head/valve cover area on the FPT engine.

3. 3

   Address Wiring

   If diagnostics proved the short is in the wiring harness, open the wire loom at the identified damage point. Splice and repair the damaged high-side and low-side wires using OEM-approved weather-sealed connectors, or replace the affected engine harness section.

4. 4

   Replace the Solenoid

   If the solenoid is internally shorted, disconnect its electrical connector. Remove the retaining bolts securing the solenoid valve to the engine.

5. 5

   Install New Solenoid

   Seat the new engine compression brake solenoid valve and torque the mounting bolts to FPT engine specifications.

6. 6

   Reassembly

   Reconnect the solenoid electrical connector and ensure the harness is routed away from high-heat or high-vibration areas.

7. 7

   Clear Codes

   Reconnect the battery. Use a diagnostic scan tool to clear the 19431 / 41F3 fault code. Run the engine and test the compression brake operation to verify the repair.