New Holland 4177 – TCU / ACM / EHR Controller / DU Module: Rear EHR Control No.3 Not Calibrated

The stored calibration values for the number 3 rear electro-hydraulic remote (EHR) valve's control lever and spool position are missing or invalid. The electronic control module relies on this calibration to accurately interpret operator commands from the in-cab lever or joystick and translate them into precise hydraulic flow. Without this data, the controller cannot guarantee correct spool movement, leading it to disable the valve and log this fault. This is a common issue that can arise after a part replacement, a loss of power, or due to component wear.

• T6.120
• T6.125
• T6.140
• T6.145
• T6.150
• T6.155
• T6.160
• T6.165
• T6.175
• T6.180
• T6010
• T6020
• T6030
• T6040
• T6050
• T6060
• T6070
• T6080
• T6090
• T6095
• T7.170
• T7.185
• T7.200
• T7.210
• T7.220
• T7.235
• T7.250
• T7.260
• T7.270
• T7030
• T7040
• T7050
• T7060
• TS100A
• TS110A
• TS115A
• TS125A
• TS135A

1. 1

   Check the tractor's diagnostic menu for other active fault codes (e.g., 4178, 4179) related to open/short circuits or communication errors, which must be addressed before attempting calibration.

2. 2

   Ensure the hydraulic fluid level is correct and the fluid is clean, as contaminated or low fluid can cause erratic hydraulic behavior.

3. 3

   Visually inspect the wiring harness and connectors leading to the No. 3 remote valve stack at the rear of the tractor for any signs of damage, corrosion, or loose connections.

4. 4

   Test the switch and lever inputs for the No. 3 remote using the tractor's built-in diagnostics ('H' menu) to determine if the control lever or switch itself is faulty.

1. 1

   Prepare tractor for calibration

   Park the tractor on a level surface, engage the parking brake, and ensure all implements are disconnected or safely lowered to the ground.

2. 2

   Access the 'H' Menu

   Turn the ignition off. Connect the diagnostic tool (part number 380000843) to the diagnostic connector, typically located on a rear cab pillar. Turn the key to the 'ON' position (do not start the engine). The instrument cluster should display 'HH MENU' or a similar indicator.

3. 3

   Navigate to EHR Calibration

   Use the tractor's instrument panel buttons (often labeled 'h', 'm', or with arrows) to navigate through the 'H' menus. Locate the menu related to EHR, remote valve, or hydraulic calibration (often designated as 'H1', 'HL', or indicated by a hydraulic symbol showing 'CAL').

4. 4

   Initiate calibration for Valve No. 3

   Select remote valve No. 3 using the increment/decrement keys. Initiate the calibration procedure, which often involves pressing a specific button sequence, such as depressing the program switch for the corresponding lever three times.

5. 5

   Perform lever calibration

   Follow the on-screen prompts on the instrument display. Move the control lever for valve No. 3 to its full raise, lower, and float positions when prompted so the system can record the electronic values at each end of the lever's travel.

6. 6

   Save calibration values

   Once the sequence is complete, the display may show 'END'. Turn the ignition key off to store the new calibration values in the controller's memory.

7. 7

   Clear codes and verify operation

   Turn the key back on, clear all fault codes through the diagnostic menu, and operate the No. 3 remote valve to confirm it is functioning correctly and that the fault code does not reappear.