Case IH 4546 – EHR (Electronic Hydraulic Remote) Controller: Front remote No.4 - under voltage

The control module has detected that the electrical voltage signal coming from the spool position sensor (potentiometer) on the #4 front electro-hydraulic remote (EHR) valve has dropped below the minimum acceptable threshold. This condition is almost always caused by a short to ground, an open circuit (broken wire) in the sensor wiring, or an internal failure of the potentiometer itself.

• Puma/Mid Range Magnum
• MAXXUM T4E
• Case IH Puma Series (e.g., 115, 165, 180, 195, 210, 225, CVX)
• Case IH Steiger Series
• Case IH Magnum / MX / TG Series

1. 1

   Ensure the in-cab control lever or switch for remote #4 is physically resting in the neutral position and is not mechanically stuck.

2. 2

   Inspect the wiring harness and connectors leading to the #4 front remote valve. Look for chafed wires, corrosion, or loose pins that could cause an open circuit or a short to ground.

3. 3

   Disconnect the sensor and check the 5V reference signal and ground at the connector. Back-probe the signal wire while connected to see if the voltage is genuinely reading below the minimum threshold (typically < 0.5V).

4. 4

   Perform a component swap test: If the valve block allows, swap the electrical connector with an adjacent, known-good remote valve (e.g., front remote #3). If the fault code changes to the #3 valve, the issue is in the wiring harness. If the fault code remains on #4, the sensor/actuator on the valve is faulty.

1. 1

   Safety Prep

   Park the machine on a level surface, lower all hydraulic implements to the ground, turn off the engine, and relieve all hydraulic pressure.

2. 2

   Access the Valve Block

   Locate the front electro-hydraulic remote valve block and identify the specific section for valve #4.

3. 3

   Harness Repair (If Applicable)

   If diagnostics point to the wiring, repair the broken wire or replace the damaged connector pigtail.

4. 4

   Replace the Sensor/Actuator

   If the wiring is intact, the potentiometer has failed. Remove the retaining hardware holding the electronic actuator head/sensor to the valve section and install the replacement part. (Note: On many modern Bosch Rexroth EHR valves used by Case IH, the sensor is integrated into the electronic driver head, meaning the actuator head or the entire valve section must be replaced).

5. 5

   Reassembly

   Securely reconnect the wiring harness to the new sensor/valve head.

6. 6

   Mandatory Calibration

   After replacing the sensor or valve section, you must perform a remote valve calibration. This is typically done through the tractor's instrument cluster 'H' menu (Calibration menu) or the AFS Pro display. This teaches the controller the new neutral, extend, and retract voltage values for the new potentiometer.