John Deere 523751.05 – HCC or BCU: Rear Hitch Control Valve Low Amps / Open Circuit Detected in M08 Stepper Motor for Hitch (Coil 1)

The control module detects an abnormally high voltage at the output to the stepper motor for the hitch (Coil 1) on leads 7058 and 7059, indicating an open circuit that disrupts current flow. As a safety reaction, the control unit deactivates the hitch control to prevent erratic operation or damage.

• 6110M
• 6120M
• 6130M
• 6145M
• 6155M
• 6175M
• 6195M
• 6110R
• 6120R
• 6130R
• 6145R
• 6155R
• 6175R
• 6195R
• 6215R
• 5090M
• 5100M
• 5100MH
• 5100ML
• 5115M
• 6125M
• 6135M
• 6140M
• 6210M
• 6230R
• 6250R
• 6090MC
• 6100MC
• 6110MC
• 6090RC
• 6100RC
• 6110RC
• 6100J
• 6105J
• 6110J
• 6115J
• 6125J
• 6135J
• 6145J
• 6155J
• 6165J
• 6180J
• 6205J
• 6210J
• 6230
• 6330
• 6430
• 5080R
• 5090R
• 5100R
• 5080RN
• 5090RN
• 5100RN
• 5620
• 5720
• 5820

1. 1

   Visually inspect the wiring harness and connectors associated with leads 7058 and 7059 (Coil 1 circuit) for signs of chafing, damage, wear, or loose pins.

2. 2

   Use a multimeter to test for continuity across the circuit to confirm if an open circuit is present.

3. 3

   Test the M08 stepper motor directly to ensure it operates correctly and has not failed internally.

1. 1

   Power Down

   Turn off the tractor and disconnect the battery to ensure safety while working on the electrical system.

2. 2

   Access the Valve

   Locate the Rear Hitch Control Valve (Rockshaft Control Valve) at the rear of the chassis.

3. 3

   Repair Wiring

   If the continuity test revealed a break in leads 7058 or 7059, repair the broken wire or replace the damaged connector terminal to restore electrical connectivity.

4. 4

   Replace the Motor/Valve

   If the wiring is good but the stepper motor has an internal open circuit, replace the stepper motor. Note: On many models, the stepper motor is integrated into the Rear Hitch Control Valve assembly and may require replacing the entire valve unit.

5. 5

   Reassemble and Reconnect

   Reconnect the wiring harness and restore battery power.

6. 6

   Reset and Calibrate

   Clear the 523751.05 diagnostic trouble code from the HCC/BCU. Perform a system reset and run the hitch calibration procedure (setting the raising and lowering deadbands) to ensure the new components are recognized and functioning normally.