Case IH 4194 – DU Module: Rear EHR No.1 Motor Mode Switch Faulty (DU Module Only)

The system has detected an invalid signal, failure, or open/short circuit originating from the #1 rear hydraulic remote motor mode switch, which is used to toggle the valve into a continuous flow state.

• Maxxum
• Magnum
• Steiger
• Quadtrac
• Puma
• Optum

1. 1

   Inspect the physical condition of the EHR #1 motor mode switch/lever on the armrest for breakage, stickiness, or looseness.

2. 2

   Perform an operational isolation test by running the hydraulic motor on a different remote (e.g., #2 or #4) to confirm the issue is isolated to the #1 switch circuit.

3. 3

   Lift or disassemble the armrest console to inspect the wiring harness and connectors leading to the EHR switch pods for pinched wires, loose connector pins, or corrosion.

4. 4

   Use the tractor's diagnostic H-menus (e.g., H3/H9) or the Case IH Electronic Service Tool (EST) to monitor the switch state live while toggling it.

5. 5

   Check for related codes (such as 4170, 4171, or 4172) that might indicate a broader harness issue or a failure at the EHR pilot head on the valve itself.

1. 1

   Prepare tractor for repair

   Park the tractor on a level surface, turn off the engine, and disconnect the battery to prevent electrical shorts.

2. 2

   Disassemble armrest console

   Carefully remove the retaining screws to disassemble the armrest console and access the underside of the EHR switch pods.

3. 3

   Disconnect switch

   Locate the electrical connector for the #1 EHR switch/pod and disconnect it.

4. 4

   Test switch continuity

   Test the switch for continuity using a multimeter. If the switch fails the continuity test (does not close/open the circuit properly), it must be replaced.

5. 5

   Remove faulty switch

   Unclip or unscrew the faulty switch or switch pod assembly from the armrest panel.

6. 6

   Install new switch

   Install the new switch/pod and securely reconnect the electrical harness.

7. 7

   Reassemble armrest console

   Reassemble the armrest console, ensuring no wires are pinched in the plastic housing.

8. 8

   Restore power

   Reconnect the battery and turn on the tractor.

9. 9

   Clear fault codes

   Clear the fault codes using the tractor's display monitor or the EST tool.

10. 10

    Test and calibrate

    Test the #1 remote in motor mode to verify the repair. (Note: Depending on the tractor model, a quick armrest or EHR calibration via the display may be required after replacing electrical components).