Case IH 18027 – Armrest Control Module (ACM): EHR 5 lever position - voltage too low (not applicable to CCM/APH _it may indicate incorrect configuration of the ACM)

The system is receiving a voltage signal from the Electro-Hydraulic Remote (EHR) valve lever #5 that has dropped below the minimum acceptable threshold. This could be a false flag caused by an incorrect configuration of the ACM, or if the lever is present, a failed potentiometer, short to ground, or open circuit.

• Magnum
• Steiger T4B
• Magnum Series
• Steiger / Quadtrac Series
• Puma Series
• Maxxum Series

1. 1

   Verify ACM Configuration: Check if the tractor actually has a 5th remote lever installed. If not, the ACM is incorrectly configured.

2. 2

   Visual Wiring Inspection: If the 5th lever is present, inspect the wiring harness for pinched wires, chafing, or disconnected plugs causing an open circuit or short to ground.

3. 3

   Swap Test (Component Isolation): Swap the electrical connector of the EHR 5 lever with an adjacent, known-good lever (e.g., EHR 4 or 6). If the fault code changes to the new position, the lever has failed. If it remains 18027, the issue is in the wiring or ACM.

4. 4

   Voltage Test: Use a multimeter to probe the lever's connector to ensure it is receiving the correct 5V reference signal from the ACM.

1. 1

   Power Down

   Turn off the tractor, remove the key, and disconnect the battery ground to prevent electrical spikes.

2. 2

   Access the Armrest

   Remove the retaining screws on the armrest control console to expose the EHR lever bank and the ACM.

3. 3

   Address Configuration (If Applicable)

   If the diagnostic check revealed a configuration error, reconnect power, connect a diagnostic tool (like Jaltest or Case IH EST), navigate to the ACM module, and change the remote valve configuration to the correct number of installed levers.

4. 4

   Replace the Lever (If Faulty)

   Disconnect the wiring harness plug from the bottom of the faulty EHR 5 lever. Remove the mounting hardware securing the lever to the armrest panel. Install the new EHR lever assembly and secure it with the mounting hardware. Reconnect the wiring harness.

5. 5

   Reassembly and Calibration

   Reinstall the armrest console cover. Reconnect the battery.

6. 6

   Calibrate

   Turn the key on and clear the stored fault codes. You must perform an EHR lever calibration procedure (often done via the EIC/display by pressing the CRPM button to access the "R1-R6" menus) so the ACM can learn the new lever's neutral, raise, and lower voltage limits.