Case IH 19206 – Engine Control Module (ECM / EDC): Short circuit to battery at low side of powerstage of external actuator relay 1

The engine's control system has detected unexpected battery voltage on the low side (ground-controlled side) of the power stage for External Actuator Relay 1. This triggers when there is a short to a power source in the wiring, an abnormally high battery voltage, or an internal short within the connected actuator itself.

• Tier 4b
• Case IH agricultural equipment (tractors, combines, sprayers)
• CNH Industrial machines with FPT electronic diesel engines

1. 1

   Check that the machine's battery voltage is within normal operating parameters and not spiking abnormally high

2. 2

   Inspect the wiring harness between the ECM, External Actuator Relay 1, and the connected actuator for chafing, melted insulation, or exposed wires shorting to a 12V/24V source

3. 3

   Disconnect the actuator connected to External Actuator Relay 1 and test it for internal short circuits

1. 1

   Power Down

   Turn off the machine and disconnect the battery to prevent further electrical damage.

2. 2

   Locate Components

   Identify External Actuator Relay 1 and the specific actuator it controls on your engine model.

3. 3

   Wiring Repair

   Trace the low-side circuit wire from the relay/actuator back to the ECM. If you find a section of the wire shorting to a battery voltage source, repair the wiring harness using approved splicing methods or replace the affected harness section.

4. 4

   Component Replacement

   If the wiring is intact, test the actuator and the relay. If the actuator has failed internally and is bridging power to the low side, replace the connected actuator.

5. 5

   Reassembly and Clearing

   Reconnect the battery, turn the key on, and use a diagnostic scan tool (such as the CNH Electronic Service Tool) to clear the fault code. Run the engine to verify the code does not return.