Case IH 1006 – Hitch Controller / EDC Module: Electronic draft control low side driver stuck on failure

The internal low-side driver circuit within the controller—which provides the ground path to activate the electronic draft control (hitch) valve solenoids—is stuck in a failed state. This prevents the module from properly commanding the raise or lower functions of the rear hitch.

• Magnum
• Steiger T4B
• Magnum Series
• Puma Series
• Steiger Series
• Maxxum Series
• Farmall Series
• CX Series

1. 1

   Inspect the wiring harness between the EDC module and the hitch control valve solenoids for chafed wires causing a short to ground or a short to 12V

2. 2

   Ensure the connectors at the EDC module and the hitch valve are fully seated, not damaged, and that the pins are tight and free of corrosion

3. 3

   Test the resistance of the raise and lower hitch valve coils to ensure they are within OEM specification and not internally shorted

4. 4

   Check the EDC valve raise and lower solenoids for sticking plungers, which can cause abnormal current draws

5. 5

   Perform a low standby pressure test on the hydraulic system (target is typically 24 - 26 bar / 348.0 - 377.0 psi) to determine if the flow compensating valve requires examination or adjustment

1. 1

   Safely Prep the Machine

   Turn off the tractor, lower the hitch to the ground (if possible), and disconnect the battery to prevent electrical spikes during repair.

2. 2

   Isolate the Solenoids

   Locate the EDC hitch control valve assembly at the rear of the tractor. Disconnect the electrical connectors to the raise and lower solenoids.

3. 3

   Test the Circuits

   Using a multimeter, check the wiring harness for continuity from the valve connectors back to the EDC controller. Verify there is no continuity to ground (which would indicate a shorted wire). Repair any damaged wiring.

4. 4

   Inspect the Valve Plungers

   If the wiring is intact, remove the solenoids from the EDC control valve. Inspect the valve plungers for sticking or binding. Clean the valve body and rectify any sticking plungers.

5. 5

   Replace Faulty Solenoids

   If a solenoid coil tests out of specification (shorted or open), replace the individual hitch valve coil.

6. 6

   Replace the EDC Controller (If Necessary)

   If the wiring harness is perfectly intact and the solenoids are functioning correctly, the 'stuck on failure' indicates that the physical low-side driver microchip inside the EDC controller has burned out or failed. The EDC module must be replaced.

7. 7

   Recalibrate

   After replacing the valve, solenoids, or the EDC controller, reconnect the battery. Use a diagnostic tool (such as the Case IH EST or Jaltest) to clear the fault codes and perform a hitch calibration procedure.