Case IH 518570-02 - ACM – ACM: EHR B extended switch circuit fault

The data from the EHR B extended switch is erratic, intermittent, or incorrect, indicating a physical circuit issue such as an open circuit, a short to ground, or a failing internal switch contact.

• MAGNUM AFS Connect
• Steiger
• Puma

1. 1

   Monitor Switch Status: Use the tractor's display monitor or an electronic service tool to view the ACM parameter list. Select the EHR B switch status and toggle the physical lever/switch to see if the module recognizes the input.

2. 2

   Visual Inspection: Inspect the multi-function handle and the EHR lever block on the armrest for physical damage, liquid spills, or debris that could jam the switch.

3. 3

   Circuit Testing: Access the wiring harness connecting the EHR B switch to the Armrest Control Module. Check for continuity, open circuits, or shorts to ground.

4. 4

   Pin Inspection: Check the connectors at both the switch and the ACM for pushed-out pins, loose connections, or corrosion.

1. 1

   Power Down

   Turn off the tractor and disconnect the battery to prevent electrical shorts while working on the armrest modules.

2. 2

   Access the Console

   Carefully remove the cover panels on the right-hand armrest console to expose the EHR lever assemblies and the ACM.

3. 3

   Isolate the Fault

   Disconnect the EHR B switch/lever harness. Use a multimeter to test the switch's internal resistance when actuated.

4. 4

   Repair Wiring

   If the switch tests fine but the harness fails continuity to the ACM, repair the broken wire or replace the sub-harness.

5. 5

   Replace the Switch/Lever

   If the switch itself has an internal open or short, remove the retaining hardware for the EHR lever block and install a new lever/encoder assembly.

6. 6

   Reassembly and Calibration

   Reconnect all harnesses, reassemble the armrest console, and reconnect the battery. Clear the inactive fault codes from the ACM and perform a functional test of the EHR B remote valve to ensure it extends and retracts properly.