Case IH 17657 (F-518400-04) - ECU – Engine Control Module (ECM): ECM 12/24 volt actuator supply 5 is shorted to ground

The Engine Control Module (ECM) monitors the voltage on its actuator supply circuits. It has detected that the voltage on Supply Circuit 5 (pins 5.07 and 6.41) has dropped to zero due to a short circuit to the ground (chassis or ground wire).

• VESTRUM CVX
• Magnum (CVT/CVX)
• Maxxum (CVX)
• Optum (CVX)
• Puma (CVX/X)
• Vestrum
• Steiger
• Quadtrac
• Axial-Flow 5150
• Axial-Flow 6150
• Axial-Flow 7150
• Axial-Flow 7250
• Axial-Flow 8250
• Axial-Flow 9250
• Patriot 3250
• Patriot 4450
• Farmlift 737
• Farmlift 742
• Case Wheel Loaders
• Graders

1. 1

   Visually inspect the main engine wiring harness for obvious signs of chafing, melting, or pinching against the engine block or chassis.

2. 2

   Disconnect the Bosch MD1CE101 ECM connectors and inspect pins 5.07 and 6.41 for corrosion, bent pins, or moisture ingress.

3. 3

   With the ECM disconnected, use a digital multimeter to check for continuity between the harness-side pins (5.07 and 6.41) and a known good chassis ground. If continuity exists, a short is present.

4. 4

   Disconnect the actuators on Supply 5 one by one, re-checking the harness for a short to ground after each disconnection. If the short disappears when a specific actuator is unplugged, that actuator is internally shorted. If the short remains with all actuators unplugged, the wiring harness itself is shorted to ground.

1. 1

   Disconnect Power

   Turn off the ignition and disconnect the negative battery cable to prevent electrical spikes.

2. 2

   Locate the Short

   Based on the diagnostic isolation test, locate the exact point of failure (either a damaged section of the wiring harness or a faulty actuator).

3. 3

   Repair the Harness

   If the wire leading from pins 5.07 or 6.41 is chafed and touching the chassis, cut out the damaged section. Splice in a new section of wire using OEM-approved crimp connectors and seal it with dual-wall adhesive heat shrink tubing to prevent moisture entry. Reroute the harness away from sharp edges or extreme heat sources.

4. 4

   Replace the Actuator

   If an actuator was found to be internally shorted to ground, unbolt and replace the faulty component.

5. 5

   Reassemble

   Reconnect all actuator and ECM connectors, ensuring the locking mechanisms click into place securely.

6. 6

   Clear Codes

   Reconnect the battery. Connect the CNH Electronic Service Tool (EST) to the machine's diagnostic port and clear the inactive fault code 17657.

7. 7

   Test Run

   Start the engine and verify that the fault code does not return and that the engine operates without derate.