Case IH 17659 (F-518406-04) - ECU – Engine Control Module (ECM): ECM 12/24 volt actuator supply 8 is shorted to ground

The Engine Control Module (ECM) has detected that the voltage on its 8th actuator supply circuit has dropped to zero due to a short circuit to the chassis or ground. The specific output pins for Supply 8 on the ECM are identified as pins 3.45 and 3.46.

• VESTRUM CVX
• Axial-Flow Combine 6150
• Axial-Flow Combine 7150
• Axial-Flow Combine 7240
• Axial-Flow Combine 7250
• Axial-Flow Combine 8240
• Axial-Flow Combine 8250
• Axial-Flow Combine 9240
• Axial-Flow Combine 9250
• Magnum Series
• Maxxum Series
• Vestrum Series
• Luxxum Series
• Farmlift Series
• Farmlift 935
• TC 5.90

1. 1

   Locate the engine harness connector that plugs into the MD1CE101 ECM and identify pins 3.45 and 3.46.

2. 2

   Visually inspect the wiring harness running from these pins to the engine actuators. Look for chafed insulation, pinched wires, or areas where the harness rubs against the engine block or frame.

3. 3

   Disconnect the ECM harness. Using a digital multimeter, measure the resistance between pins 3.45/3.46 on the harness side and a known good chassis ground. If there is continuity, a short to ground is present.

4. 4

   Disconnect the actuators powered by Supply 8 one by one. If the short to ground disappears when a specific actuator is unplugged, that actuator is internally shorted. If the short remains, the wiring harness itself is damaged.

1. 1

   Disconnect Power

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

2. 2

   Access the ECM

   Locate the Bosch MD1CE101 ECM on the engine block or firewall.

3. 3

   Repair the Wiring

   If the diagnostic checks revealed a short in the harness, open the wire loom at the damaged section. Splice and solder the damaged wires for pins 3.45 or 3.46, and seal them with heat-shrink tubing.

4. 4

   Replace Faulty Actuator

   If an actuator was found to be internally shorted to ground during step 4 of the diagnostics, remove and replace the faulty actuator.

5. 5

   Reassemble and Clear Codes

   Reconnect all harness connectors and the battery. Connect a diagnostic tool (such as the CNH Electronic Service Tool (EST) or a compatible scanner like TEXA IDC5) to the machine's OBD/diagnostic port. Clear the inactive fault code 17659 and run the engine to verify the code does not return.