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Home >> Lincoln >> 2019 >> Navigator Reserve >> Repair and Diagnosis (Single Page) >> Transmission >> Transmission Control Systems >> Four-Wheel Drive Systems >> Diagnosis And Testing >> Four-Wheel Drive Systems - Vehicles With: 2-Speed Torque On Demand Transfer Case >> Pinpoint Tests >> Pinpoint Test A : Four-Wheel Drive (4WD) System Functional Test >> Pinpoint Test A : Four-Wheel Drive (4WD) System Functional Test
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Pinpoint Test A : Four-Wheel Drive (4WD) System Functional Test

NOTE: 4X4 High and 4X4 Low are not intended for driving on hard/dry surfaces. Using these modes while driving on these surfaces may produce noises like intermittent clunking, but does not damage driveline components.

  1. A1 FOUR-WHEEL DRIVE (4WD) SYSTEM FUNCTIONAL TEST

    NOTE: 4X4 High and 4X4 Low are not intended for driving on hard/dry surfaces. Using these modes while driving on these surfaces may produce noises like intermittent clunking, but does not damage driveline components.

    • Ignition ON.

    • Gear Selector in Park..

    • Enter the following diagnostic mode:

      • TCCM KOEO Self-test.

      • ATCM KOEO Self-test.

    Are DTCs retrieved? 

    Yes  REFER to DTC Chart: TCCM . REFER to DTC Chart: All-Terrain Control Module .
    No  GO to  A2

  2. A2 CHECK ROTARY SWITCH

    • Gear Selector in Park.

    • Start Engine.

    • Enter the Diagnostic Mode: Datalogger >> ATCM.

    • Monitor the PIDs LAST_DIR_CLCK_RT and LAST_DIR_CNTR_LEFT while rotating the 4x4 Switch Module knob clockwise and counterclockwise.

    Do the PIDs update correctly indicating the last direction the rotary knob was rotated? 

    Yes  GO to  A3.
    No  INSTALL a new ATCM, REFER to: Mode Select Switch (MSS) .

  3. A3 CHECK FOR WIND-UP IN 2H MODE

    • NORMAL drive mode.

    • Gear Selector in Park.

    • Start Engine.

    • Enter the Diagnostic Mode: Datalogger >> TCCM.

    • Monitor the PID 4x4_SW.

    Does the 4x4_SW display 2WD? 

    Yes  The TCCM recognizes a valid input from the ATCM. GO to  A4
    No  Perform Pinpoint test for no ATCM communication. REFER to: Communications Network - System Operation and Component Description .

  4. A4 CHECK THE IPC INDICATOR AND/OR MESSAGE CENTER WHILE COMMANDING 2H

    • NORMAL drive mode.

    • Selector Lever in Park.

    • Turn ignition OFF.

    • Start Engine.

    Does the 2H indicator momentarily illuminate in the IPC message center? 

    Yes  The TCCM was able to move the shift motor to the 2H position. GO to  A5
    No  GO to Pinpoint Test G 

  5. A5 CHECK THE IWE DISENGAGEMENT

    NOTE: The TCCM may command the IWEs to engage during 2H operation to warm up the front axle.

    • With the vehicle in NEUTRAL, position it on a hoist. Raise the vehicle until all 4 wheels are off the ground. REFER to: Jacking and Lifting .

    • NOTE: The engine must be idling during the following steps to supply the vacuum required for the IWEs to disengage.

      Engine running.

    • Gear selector in Neutral.

    • NORMAL drive mode.

    • Enter the following diagnostic mode: Datalogger >> TCCM

    • 6 Command IWE_OS# to NO

    • Rotate the LH front tire one revolution forward and one revolution backward while observing the LH front halfshaft.

    • Rotate the RH front tire one revolution forward and one revolution backward while observing the RH front halfshaft.

    Is wind-up present in turns? 

    Yes  End Output State Control. GO to  A6
    No  End Output State Control. GO to Pinpoint Test E 

  6. A6 CHECK THE IWE ENGAGEMENT

    • Vehicle on hoist with all 4 wheels off the ground.

    • Engine running.

    • Gear selector in Neutral.

    • DEEP CONDITIONS drive mode.

    • Rotate the LH front tire one revolution forward and one revolution backward while observing the LH front halfshaft.

    • Rotate the RH front tire one revolution forward and one revolution backward while observing the RH front halfshaft.

    Is wind-up present in turns? 

    Yes  The front axle is operating properly at this time. GO to  A7
    No  GO to Pinpoint Test E 

  7. A7 CHECK TORQUE ON DEMAND CLUTCH OPERATION

    • DEEP CONDITIONS drive mode.

    • Enter the following diagnostic mode: Datalogger >> TCCM.

    • Command 4WD_CLTCH_OUT # to 70-80%.

    Is wind-up / vehicle bind present? 

    Yes  The TOD clutch is transmitting torque as expected. GO to  A8
    No  The TOD clutch is slipping / not transferring torque. CHECK the transfer case. REFER to: Transfer Case - Vehicles With: 2-Speed Torque On Demand Transfer Case .

  8. A8 CHECK RANGE FORK OPERATION

    • Engine running.

    • Gear selector in NEUTRAL, vehicle stopped.

    • Rotate the drive mode switch to SLOW CLIMB drive mode.

    Does 4L indicator illuminate on the IPC? 

    Yes  The shift motor moved to engage 4L. GO to  A9
    No  GO to Pinpoint Test G 

  9. A9 CHECK 4L OPERATION

    • SLOW CLIMB drive mode.

    • Drive the vehicle up to 10 mph.

    Did the transfer case engage LOW range? 

    Yes  GO to  A10
    No  The shift motor moved to engage 4L, but the transfer case did not provide a reduced gear ratio. CHECK the transfer case. REFER to: Transfer Case - Vehicles With: 2-Speed Torque On Demand Transfer Case .

  10. A10 CHECK FOR WIND-UP IN 2H MODE WITH IWES ENGAGED

    • NORMAL drive mode.

    • Enter the following diagnostic mode: datalogger >> TCCM.

    • Command IWE_OS# to YES

    • 4 Drive the vehicle on a dry, hard surface while full lock turns.

    Is wind-up / vehicle bind present? 

    Yes  Exit Output State Control. The transfer case is unable to disengage 4x4. CHECK the transfer case. REFER to: Transfer Case - Vehicles With: 2-Speed Torque On Demand Transfer Case .
    No  Exit Output State Control. The 4WD system is operating as designed
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