Case IH 7017 (746.05) - DEC – Transmission Controller: Differential lock solenoid - open circuit

This fault code indicates that the control module is not detecting the expected electrical continuity through the differential lock solenoid circuit. An 'open circuit' condition typically means there is a broken wire in the harness, a disconnected or corroded electrical plug, or the internal coil of the solenoid itself has failed and broken continuity.

• VESTRUM CVX
• Maxxum 5120
• Maxxum 5130
• Maxxum 5140
• Maxxum 5220
• Maxxum 5230
• Maxxum 5240
• Maxxum 5250
• 3220
• 3230
• 4210
• 4230
• 4240
• Magnum Series
• Puma Series
• Steiger Series

1. 1

   Locate the differential lock solenoid on the transmission/rear axle housing. Inspect the 2-terminal plug-and-harness connector for physical damage, severe corrosion, or backed-out pins.

2. 2

   Disconnect the harness from the solenoid. Using a multimeter, check the wiring harness from the solenoid connector back to the transmission controller for any breaks or chafing.

3. 3

   Measure the resistance (Ohms) across the two terminals on the differential lock solenoid itself. If the multimeter reads 'OL' (infinite resistance/out of limits), the solenoid coil is internally open and the solenoid must be replaced.

1. 1

   Prepare machine

   Park the tractor on a level surface, engage the parking brake, turn off the engine, and relieve any residual hydraulic pressure if required by your specific model's service manual.

2. 2

   Clean area

   Clean the area around the differential lock solenoid on the transmission valve block to prevent dirt from entering the hydraulic system.

3. 3

   Disconnect solenoid

   Unplug the 2-terminal electrical connector from the solenoid.

4. 4

   Repair wiring

   If the diagnostic tests proved the wiring harness was at fault, repair the broken wire or splice in a new connector pigtail.

5. 5

   Remove faulty solenoid

   If the solenoid failed the resistance test, unscrew and remove the faulty differential lock solenoid valve from the housing.

6. 6

   Install new solenoid

   Lubricate the O-rings on the new solenoid with clean hydraulic oil and thread it into the valve block. Tighten to the OEM torque specification.

7. 7

   Reconnect harness

   Reconnect the electrical harness.

8. 8

   Test system

   Turn the key on, clear the fault codes from the transmission controller, and test the differential lock switch in the cab to ensure the code does not return and the lock engages properly.