Case IH 18327 (4163.02, 4163.03, 4163.04, 518569.07) - ACML – ACML / ACM (Armrest Control Module): MFH EHR1 Retract Switch ACML - error state

The system is detecting an electrical fault or a stuck switch on the joystick for the #1 hydraulic remote retract function.

• MAXXUM T4E
• VESTRUM CVX
• Magnum Series (235, 250, 290, 340)
• Steiger Series (350, 370, 400, 450, 500, 550, 600)
• Puma Series (165, 180, 195, 210, 225)
• Maxxum Series (135 Multicontroller)

1. 1

   Physical Inspection: Inspect the EHR1 switch on the Multi-Function Handle for physical damage, sticking, or debris holding the switch down.

2. 2

   Monitor Switch State: Use the tractor's display (Pro 700 / AFS Pro 1200) or the Electronic Service Tool (EST) to view the live status of the switch. Navigate to the diagnostic menu (often the 'H' menu or 'HH MENU') to monitor the inputs for the MFH EHR1 Retract Switch (often labeled as input d179). Verify if the state changes when the switch is pressed and released.

3. 3

   Wiring & Connector Check: Check the wiring harness and the X846 connector (Multi Function Handle Electronic Module connector) that links the MFH to the Armrest Control Unit (GARU). Look for pinched wires, corrosion, or shorts to ground/power.

4. 4

   Clear and Retest: Clear the fault codes via the display (using the H8 clear function or EST) and cycle the key to see if the code returns immediately upon power-up.

1. 1

   Turn off tractor and disconnect battery

   Turn off the tractor and disconnect the battery to prevent electrical spikes.

2. 2

   Disassemble armrest console covers

   Disassemble the armrest console covers to gain access to the base of the Multi-Function Handle.

3. 3

   Disconnect electrical connector

   Disconnect the main electrical connector (X846) from the MFH.

4. 4

   Remove Multi-Function Handle

   Remove the mounting hardware securing the Multi-Function Handle to the armrest and remove the handle.

5. 5

   Install new handle or switch

   Install the new Multi-Function Handle (or replacement switch assembly) and secure the mounting hardware.

6. 6

   Reconnect connector and reassemble

   Reconnect the X846 electrical connector and reassemble the armrest covers.

7. 7

   Reconnect battery and turn key ON

   Reconnect the battery and turn the key switch ON.

8. 8

   Calibrate EHR valves or MFH

   Enter the calibration menu (HJ menu). The lower display will momentarily show 'Ehr_' followed by 'Ehr1', and an audible beep will indicate the valve has been recognized. Follow the prompts to recognize all subsequent valves (Ehr2, Ehr3, etc.).

9. 9

   Clear codes and test

   Clear any stored fault codes and test the EHR1 retract function for normal operation.