Case IH 2174 – EHR (Electronic Hitch Control) module: Hitch position (lift arm) potentiometer circuit failed, position potentiometer signal voltage outside the 0.3 to 5.0 volt limit.

When this code is active, the system enters a "LIMP" category response. The hitch enable light will illuminate, and the 3-point hitch will only operate for 1.5 seconds at a time when using the cab switches or remote fender switches.

• Steiger T4B
• Maxxum
• Magnum
• Puma
• CX series

1. 1

   Check that the hitch position potentiometer is seated correctly into its mounting bracket and that the retaining nut is tight

2. 2

   Verify that the potentiometer link arm is located correctly and that the retaining Allen screw has not slipped or loosened

3. 3

   Use a multimeter to check the signal voltage of the hitch position potentiometer circuit (expected range is 0.3V to 5.0V)

4. 4

   Inspect the wiring harness between the potentiometer and the EHR module for a short to voltage (above 5 volts) or a short to ground

1. 1

   Park and Secure

   Park the tractor on level ground, lower the hitch (if possible), turn off the engine, and remove the key.

2. 2

   Locate the Sensor

   Locate the hitch position potentiometer, which is mounted on the rear rockshaft/lift arm assembly at the back of the tractor.

3. 3

   Inspect and Tighten

   Inspect the mechanical linkage connecting the lift arm to the potentiometer. If the linkage has slipped, realign it, tighten the Allen screw, and clear the code to see if normal operation resumes.

4. 4

   Test the Circuit

   Disconnect the 3-pin connector at the potentiometer. Check for a 5V reference signal and a good ground from the EHR module.

5. 5

   Replace the Sensor

   If the wiring is intact and the mechanical linkage is secure, the potentiometer itself has failed internally. Unbolt the old potentiometer, disconnect the linkage arm, and install the new sensor.

6. 6

   Recalibrate

   After replacing the potentiometer, you must perform the EHR / Hitch Calibration procedure via the tractor's instrument cluster or diagnostic tool to teach the module the new upper and lower voltage limits for the lift arms.