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Pinpoint Test A: Electronic Shift Functional Test

CAUTION: The function test must be carried out on a hard surface in a vacant area without traffic.
  1. A1 CHECK FOR 2WD INDICATED 
    • Make sure the hublocks are in the AUTO position.
    • Start the vehicle and allow to idle.
    • Apply the brake pedal and hold.
    • Shift the transmission to NEUTRAL.
    • Turn the mode select switch (MSS) to 2WD while holding the shift conditions.
    • Observe the 4WD and 4WD LOW indicators.
    • Are both indicators off? 
    • Yes  : GO to A3.
    • No  : GO to A2.
  2. A2 CHECK FOR THE PRESENCE OF 4WD 
      CAUTION: Make sure there is a clear area behind the vehicle before backing up.
    • Shift the transmission to REVERSE and back the vehicle up 3.0 meters (10 feet) to relieve driveline wind-up.
    • Drive the vehicle forward for 3.0 meters (10 feet) and stop.
    • Press the brake pedal and hold.
    • Shift the transmission to NEUTRAL. Hold the shift conditions for 20 seconds.
    • Execute tight turns on a hard surface.
    • Check for the presence of driveline wind-up and tire scuff.
    • Is driveline wind-up and tire scuff present? 
  3. A3 CHECK INDICATOR PROVE-OUT 
    • Key in OFF position.
    • Turn the ignition switch to start and observe the 4WD and 4WD LOW indicators for prove-out.
    • Did the indicators prove out? 
    • Yes  : GO to A4.
    • No  : REPAIR the instrument cluster as necessary. refer to INSTRUMENT CLUSTER .
  4. A4 VERIFY SHIFT TO 4WD 
    • Turn the MSS to 4WD.
    • Listen for relay clicks and gearmotor operation.
    • Wait for 20 seconds after the MSS is turned to 4WD. (The system will use up to five cycles of shift attempts trying to engage 4WD.)
    • Is the 4WD indicator ON? 
    • Yes  : GO to A6.
    • No  : GO to A5.
  5. A5 ATTEMPT MECHANICAL ASSIST ENGAGEMENT 
    • Drive the vehicle for at least 20 seconds.
    • Stop the vehicle.
    • Observe the 4WD indicator.
    • Is the 4WD indicator ON? 
  6. A6 CHECK FOR MECHANICAL ENGAGEMENT OF 4WD 
    • Drive the vehicle for two minutes above 16 km/h (10 mph).
    • Execute tight turns on a hard surface.
    • Check for the presence of driveline wind-up and tire scuff.
    • Is driveline wind-up and tire scuff present? 
    • Yes  : GO to A9.
    • No  : 4WD did not mechanically engage.

    RETRIEVE 4WD control module self-test DTCs. If a self-test DTC related to the concern is retrieved, REFER to the 4WD CONTROL MODULE DIAGNOSTIC TROUBLE CODE (DTC) INDEX . If no DTC related to the concern is retrieved, GO to A7.

  7. A7 CHECK FOR FRONT AXLE ENGAGEMENT 
    • Raise and support the front tires off the ground until they can be spun freely. refer to JACKING & LIFTING .
    • Rotate the left front tire one revolution forward and one revolution backward while observing the left front axle shaft and universal joint.
    • Rotate the right front tire one revolution forward and one revolution backward while observing the right front axle shaft and universal joint.
    • Did both front axle shafts rotate? 
  8. A8 CHECK FOR FRONT AXLE/DIFFERENTIAL ENGAGEMENT 
    • Rotate the front driveshaft.
    • Does either front axle shaft turn? 
  9. A9 VALIDATE FOR CORRECT OPERATION ON 4WD LOW SHIFT CONDITIONS 
    • While driving the vehicle forward, turn the MSS to 4WD LOW while observing the indicators for five seconds.
    • Shift the MSS to 4WD.
    • Stop the vehicle and apply the parking brake.
    • For automatic transmission, shift the transmission to PARK and release the brake pedal. For manual transmission, shift the transmission to NEUTRAL and release the clutch pedal.
    • Is the 4WD LOW indicator ON? 
  10. A10 CHECK THE 4WD LOW INDICATOR ON IN ERROR 
    • Turn the MSS to 4WD LOW.
    • Apply and hold the brake pedal.
    • Is the 4WD LOW indicator OFF? 
  11. A11 CHECK THE 4WD LOW INDICATOR FOR ON IN 4WD LOW 
    • Shift the transmission to NEUTRAL.
    • Listen for relay clicks and gearmotor operation.
    • Hold the shift conditions for 20 seconds. (The system will use up to five cycles of shift attempts trying to engage 4WD LOW.)
    • Is the 4WD LOW indicator ON? 
    • Yes  : GO to A13.
    • No  : GO to A12.
  12. A12 ATTEMPT MECHANICAL ASSIST OF 4WD LOW ENGAGEMENT 
      CAUTION: Make sure there is a clear area behind the vehicle before backing up.
    • Shift the transmission to REVERSE and back the vehicle up 3.0 meters (10 feet) to relieve driveline wind-up and stop.
    • Drive the vehicle forward for 3.0 meters (10 feet) and stop.
    • Apply the brake pedal and hold.
    • For automatic transmission, shift the transmission to NEUTRAL. For manual transmission, press the clutch pedal and hold. Hold all shift conditions for 20 seconds.
    • Observe the 4WD LOW indicator.
    • Is the 4WD LOW indicator ON? 
  13. A13 CHECK FOR MECHANICAL ENGAGEMENT OF 4WD LOW 
      NOTE: Driveline wind-up and tire scuff is present in both 4WD and 4WD LOW. However, vehicle speed is severely limited in 4WD LOW.
    • Execute tight turns on a hard surface.
    • Check for the presence of driveline wind-up, tire scuff and reduced vehicle speed.
    • Is driveline wind-up, tire scuff and reduced speed present? 
    • Yes  : GO to A14.
    • No  : 4WD LOW did not mechanically engage.

    RETRIEVE 4WD control module self-test DTCs. If a self-test DTC related to the concern is retrieved, REFER to the 4WD CONTROL MODULE DIAGNOSTIC TROUBLE CODE (DTC) INDEX . If no DTC related to the concern is retrieved, Go to PINPOINT TEST D: THE VEHICLE DOES NOT SHIFT BETWEEN 4WD AND 4WD LOW MODES CORRECTLY .

  14. A14 CHECK FOR CORRECT INDICATOR OPERATION ON 4WD LOW DISENGAGEMENT 
    • While driving the vehicle forward, turn the MSS to 4WD while observing the indicators.
    • Turn the MSS to 4WD LOW.
    • Stop the vehicle and apply the parking brake.
    • Shift the transmission to PARK and release the brake pedal.
    • Is the 4WD LOW indicator ON? 
  15. A15 CHECK THE 4WD LOW INDICATOR 
    • Turn the MSS to 4WD.
    • Apply and hold the brake pedal.
    • Is the 4WD LOW indicator ON? 
  16. A16 CHECK FOR 4WD LOW INDICATOR OFF IN 4WD 
    • Press and hold the brake pedal.
    • Shift the transmission to NEUTRAL.
    • Listen for relay clicks and gearmotor operation.
    • Hold the shift conditions for 20 seconds. (The system will use up to five cycles of shift attempts trying to engage 4WD.)
    • Is the 4WD LOW indicator OFF? 
    • Yes  : GO to A18.
    • No  : GO to A17.
  17. A17 ATTEMPT MECHANICAL ASSIST OF 4WD LOW DISENGAGEMENT 
    • Drive the vehicle forward above 8 km/h (5 mph) for at least five seconds.
    • Stop the vehicle.
    • Apply the brake pedal and hold.
    • Shift the transmission to NEUTRAL. Hold all shift conditions for 20 seconds.
    • Observe the 4WD LOW indicator.
    • Is the 4WD LOW indicator OFF? 
  18. A18 CHECK FOR MECHANICAL 4WD LOW DISENGAGEMENT AND 4WD ENGAGEMENT 
    • Apply the brake.
      • CAUTION: Make sure there is a clear area behind the vehicle before backing up.
    • Shift the transmission to REVERSE and back the vehicle up 3.0 meters (10 feet) to relieve driveline wind-up.
    • Stop the vehicle.
    • Drive the vehicle forward and execute tight turns on a hard surface.
      • NOTE: Driveline wind-up and tire scuff is present in both 4WD and 4WD LOW. However, vehicle speed is severely limited in 4WD LOW.
    • Verify the presence of driveline wind-up and tire scuff. Also verify the increased vehicle speed from when 4WD LOW was engaged.
    • Did 4WD engage and the vehicle speed increase? 
    • Yes  : GO to A19.
    • No  : 4WD LOW is mechanically bound or locked. REPAIR the transfer case as necessary. refer to TRANSFER CASE .
  19. A19 CHECK THE 4WD TO 2WD SHIFT 
    • Stop the vehicle.
    • Turn the MSS to 2WD and wait 20 seconds.
    • Listen for relay clicks and gearmotor operation.
    • Are the 4WD and 4WD LOW indicators OFF? 
    • Yes  : GO to A21.
    • No  : GO to A20.
  20. A20 ATTEMPT MECHANICAL ASSIST OF 4WD DISENGAGEMENT 
    • Drive the vehicle forward for at least 20 seconds.
    • Stop the vehicle.
    • Observe the 4WD and 4WD LOW indicators.
    • Are the 4WD and 4WD LOW indicators OFF? 
  21. A21 VERIFY THE HUBLOCKS DISENGAGE 
    • Raise and support the front tires off the ground until they can be spun freely. refer to JACKING & LIFTING .
    • Rotate the left front tire one revolution forward and one revolution backward, while observing the left front axle shaft and universal joint.
    • Rotate the right front tire one revolution forward and one revolution backward, while observing the right front axle shaft and universal joint.
    • Did either axle shaft rotate? 
  22. A22 VERIFY THE TRANSFER CASE MECHANICALLY DISENGAGED 
    • Apply the parking brake.
    • Rotate the front driveshaft.
    • Does the front driveshaft turn? 
    • Yes  : GO to A23.
    • No  : The transfer case did not disengage from 4WD. REPAIR the transfer case as necessary. refer to TRANSFER CASE .
  23. A23 VERIFY THE HUBLOCKS WILL LOCK MANUALLY 
    • Turn both hublocks to the LOCK position.
    • Rotate the left front tire one revolution forward and one revolution backward while observing the left front axle shaft and universal joint.
    • Rotate the right front tire one revolution forward and one revolution backward while observing the right front axle shaft and universal joint.
    • Do both axles rotate? 
    • Yes  : GO to A24.
    • No  : INSTALL a new hublock. REFER to HUBLOCK  in this article.
  24. A24 VERIFY THE HUBLOCKS WILL UNLOCK MANUALLY 
    • Turn both hublocks to the AUTO position.
    • Rotate the left front tire one revolution forward and one revolution backward while observing the left front axle shaft and universal joint.
    • Rotate the right front tire one revolution forward and one revolution backward while observing the right front axle shaft and universal joint.
    • Does either axle rotate? 
    • Yes  : INSTALL a new hublock. REFER to HUBLOCK  in this article.
    • No  : The transfer case is operating correctly. INSTRUCT the customer on correct system operation.
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