Case IH 518564-03 - ACM – ACM: ACM: EHR lever F voltage high

The signal voltage from the potentiometer inside EHR Lever 6 is exceeding the maximum expected threshold. A "voltage high" code indicates the signal is likely shorted to a 5V or 12V power source, or the sensor ground is open.

• MAGNUM AFS Connect
• Magnum
• Steiger
• Quadtrac
• Puma
• Maxxum
• T6
• T7
• T8
• T9

1. 1

   Check Calibration Values: Connect the Electronic Service Tool (EST) or navigate to the tractor's diagnostic display to view the live voltage values for EHR Lever 6 (Lever F).

2. 2

   Inspect Wiring: If the voltage is pegged high (e.g., at a full 5V reference voltage), inspect the wiring harness between the EHR lever and the ACM. Look for a short to a power source or a broken/corroded sensor ground wire.

3. 3

   Check for Recent Replacements: If the ACM or the EHR lever was recently replaced or updated, the lever may simply be uncalibrated.

1. 1

   Attempt Calibration

   If the lever is uncalibrated, perform the EHR lever calibration procedure using the EST or the tractor's H-Menu/display. Move the lever through its full range of motion (Float, Lower, Neutral, Raise) so the ACM can learn the potentiometer values.

2. 2

   Clear and Retest

   After calibration, clear the fault codes. If the code 518564-03 returns immediately, the issue is a hard fault in the hardware.

3. 3

   Test the Circuit

   Disconnect the EHR lever and test the harness side for proper 5V reference and ground. If the harness tests good, the potentiometer inside the lever has failed.

4. 4

   Replace the Lever

   Remove the armrest trim to access the EHR control unit. Disconnect the electrical connector for Lever F and physically remove the faulty lever assembly.

5. 5

   Install and Recalibrate

   Install the new EHR lever. Crucial step: You must perform the EHR lever calibration procedure again after installing the new part, or the ACM will not recognize its specific voltage sweeps and will throw an implausibility error.