Case IH 4370 – EHR (Electro-Hydraulic Remote) Controller or AUX (Auxiliary Valve) Controller: EHR pressure sensor - out of range high

The signal voltage returning from the EHR pressure sensor to the controller has exceeded the maximum expected threshold (typically near 5 volts). This is usually caused by an internal sensor failure, an open circuit in the sensor wiring harness, or a short to power in the harness.

• Steiger T4B
• Magnum series (MX Magnum, Magnum 235-340 Series 4)
• Steiger series (ST620)
• Puma series

1. 1

   Visually inspect the wiring harness leading to the EHR pressure sensor for chafing, pinched wires, or disconnected plugs.

2. 2

   Use a multimeter to check the sensor wiring harness for an open circuit or a short to a power source.

3. 3

   Test the resistance of the EHR pressure sensor and verify that the controller is sending the correct reference voltage (usually 5V) to the sensor plug.

4. 4

   Verify continuity from the instrumentation/EHR controller to the sensor to rule out a controller failure.

1. 1

   Turn off the tractor and relieve all hydraulic pressure from the remote valve system to prevent fluid injection injuries.

2. 2

   Locate the broken EHR pressure sensor on the rear remote valve block.

3. 3

   Disconnect the electrical connector from the sensor.

4. 4

   Unthread the faulty pressure sensor from the hydraulic valve block.

5. 5

   Install the new EHR pressure sensor (ensure any required O-rings are seated properly) and tighten to OEM torque specifications.

6. 6

   Reconnect the electrical harness.

7. 7

   Power on the tractor, clear the active fault codes from the EHR/AUX controller, and test the remote valves for proper operation.