Case IH 18254 (517814.03, 517814.04, 518559.02, 518559.03, 518559.04) - ACML – ACML: EHR1 Lever Position ACML - error state

The system is detecting an implausible signal, open circuit, or error state regarding the position of the Electrohydraulic Remote (EHR) valve lever #1. This is typically caused by poor electrical contact due to electrical contamination or voltage fluctuations in the system that generate false error codes on the CAN bus.

• MAXXUM T4E
• VESTRUM CVX
• All models with EHR valves
• Case IH Puma (165, 180, 200, 210)
• Case IH Optum (Tier 4b-TMR & Stage V)
• Case IH Maxxum (100-140, 125, 135 Multicontroller)
• Case IH Magnum (290, 315)

1. 1

   Inspect the physical EHR 1 lever and the surrounding panel for dirt, debris, or liquid intrusion that could cause electrical contamination and poor contact.

2. 2

   Monitor the tractor's system voltage to ensure there are no severe fluctuations reaching the ACML, which can trigger false CAN signal errors.

3. 3

   Inspect the wiring harness connecting the EHR lever panel to the ACML for chafing, open circuits, or short circuits to ground.

4. 4

   Verify the main hydraulic lockout rocker switch is functioning correctly, as failures here can cascade or present alongside EHR lever faults.

1. 1

   Clean Contacts

   Disconnect the battery. Remove the EHR lever panel from the armrest and thoroughly clean the electrical connectors and lever contacts using an approved electrical contact cleaner to resolve any electrical contamination.

2. 2

   Secure Connections

   Reconnect the panel, ensuring the harness is routed correctly without tension, and verify the connector is fully seated to prevent voltage drops.

3. 3

   Clear and Retest

   Reconnect the battery, clear the fault codes from the ACML, and cycle the EHR 1 lever to see if the code returns.

4. 4

   Replace Components

   If the code persists and the wiring is intact, the internal potentiometer/switch of the EHR lever is likely failed. Replace the specific EHR rocker switch/lever or the entire EHR lever panel assembly.

5. 5

   Software/Calibration

   Ensure the ACML software is up to date, as software updates are frequently issued to address CAN signal sensitivity and voltage fluctuation errors.