Case IH 518565-06 - ACM – ACM: EHR lever G (Lever 7) voltage low

The system has detected that the voltage signal from the potentiometer inside EHR lever G is below the acceptable lower limit. This typically indicates an open circuit, a short to ground in the signal wire, or a complete internal failure of the lever's potentiometer.

• MAGNUM AFS Connect
• Case IH Magnum Series
• Case IH Steiger / Quadtrac Series
• Case IH Optum / Puma Series

1. 1

   Verify ACM Configuration: Check the tractor's display or use the Electronic Service Tool (EST) to ensure the ACM is configured correctly and not looking for an uninstalled lever.

2. 2

   Inspect Wiring and Connectors: Remove the armrest cover and inspect the wiring harness connecting the EHR lever to the ACM for pinched wires, chafing, or loose/corroded pins.

3. 3

   Test Voltages: Verify that the lever is receiving the 5-volt reference signal and a good ground from the ACM.

4. 4

   Back-probe the signal wire while moving the lever. If the voltage remains near 0V despite a good 5V supply and ground, the internal potentiometer has failed.

5. 5

   Attempt Calibration: Try to recalibrate the EHR levers via the tractor's display monitor. If calibration fails immediately due to an out-of-range signal, the lever must be replaced.

1. 1

2. 2

   Preparation

   Park the machine on a level surface, turn off the engine, and disconnect the battery to prevent electrical spikes.

3. 3

   Access the Lever Block

   Remove the retaining screws for the right-hand armrest control cover to expose the ACM and the EHR lever block assembly.

4. 4

   Remove faulty lever

   Disconnect the electrical harness connector from the faulty EHR lever (Lever G/7). Remove the mounting screws/clips securing the specific EHR lever to the armrest console and pull the faulty lever assembly out.

5. 5

   Install new lever

   Insert the new EHR lever into the console and secure it with the mounting hardware. Reconnect the electrical harness.

6. 6

   Reassembly

   Reinstall the armrest cover and reconnect the tractor's battery.

7. 7

   Calibrate EHR lever

   Power on the tractor. You must perform the EHR lever calibration procedure using the tractor's display monitor or the EST. This allows the ACM to learn the new potentiometer's minimum, maximum, and neutral voltage values.