Case IH P15 – Transmission / Chassis Controller: Differential Lock Solenoid Stuck Off

The transmission/chassis controller has detected that the differential lock solenoid is stuck in the "off" position. This is caused by a faulty solenoid, a faulty wiring harness, or a failure in the electronic management unit.

• MXM
• MXM Series
• MXM120
• MXM130
• MXM140
• MXM155
• MXM175
• MXM190
• Maxxum Series
• 3200 series
• 4200 series
• 5100 series
• 5200 series

1. 1

   Check the digital display for any other active error codes that might indicate a broader electrical failure.

2. 2

   Disconnect the differential lock solenoid connector (C042).

3. 3

   Turn the keystart ON and use a multimeter to verify if the solenoid is receiving the correct voltage signal from the ECU.

1. 1

   Inspect connector

   Inspect the 2-terminal plug-and-harness connector at the differential lock solenoid for dirt, moisture, or corrosion. Clean if necessary.

2. 2

   Test solenoid resistance

   Test the resistance of the solenoid coil. If it is out of specification (open or shorted internally), remove the retaining nut/bolt and slide the old solenoid off the hydraulic valve bank.

3. 3

   Install new solenoid

   Install the new differential lock solenoid and plug in the harness.

4. 4

   Clear error code

   Clear the error code from the system.

5. 5

   Test system

   Test the system for normal operation. Note: Do not depress the brake pedals during the differential lock test, as this automatically disengages the diff lock on these models.