When Monitored

This diagnostic runs continuously when the following conditions are met:

• CONDITION 1: 
  • Engine speed is above 700 rpm.
  • Controller Area Network (CAN) signals are valid (No CAN DTCs set).
  • No Front Axle Disconnect Actuator circuit DTCs set.
• CONDITION 2: 
  • CAN signals are valid (No CAN DTCs set).
  • No Front Axle Disconnect (FAD) circuit DTCs set.
• CONDITION 3: 
  • Engine speed is above 700 rpm.
  • CAN signals are valid (No CAN DTCs set).
  • No FAD circuit DTCs set.
• CONDITION 4: 
  • No Electronic Control Unit (ECU) memory DTCs set.
  • No FAD circuit DTCs set.

Set Conditions: 

• CONDITION 1  : Initial Calibration at manufacturing End Of Line (EOL) either aborted or failed due to possible hardware fault preventing completion of learn routine.
• CONDITION 2  : Regular calibration routine to compensate for clutch wear did not complete for more than 20 key cycles. (Possible hardware fault preventing completion of learn routine.)
• CONDITION 3:  Cannot find reference position for incremental position sensor despite 3 consecutive retries. Learn routine exceeded allowed time duration for completion. (Possible hardware fault preventing completion of learn routine.)
• CONDITION 4  : Initial calibration not performed after re-flash of Drivetrain Control Module (DTCM). (Manually request relearn with scan tool.)

Default Actions: 

• Service telltale lamp will be illuminated and on-screen message to service 4WD system will be displayed.
• T-CASE SHIFTING: Depending on failure conditions, disengage clutch and 2WD mode only, or lock clutch completely.
• FAD: Depending on failure conditions, FAD will be disengaged or engaged.
• FRONT AXLE LOCKER ACTUATOR: Normal Operation.
• REAR AXLE LOCKER ACTUATOR: Normal Operation.