2007 Commander XK Factory Service Manual 8 - ELECTRICAL

STANDARD PROCEDURE

LIFTGATE ADJUSTMENT

In order for the power liftgate system to function properly the liftgate must move freely and smoothly. The power liftgate system can accommodate for some minor changes in the effort required to move the liftgate. However, in extreme conditions the liftgate may need to be mechanically adjusted for proper fit and finish. (Refer to 23 - BODY/DECKLID/HATCH/LIFTGATE/TAILGATE/LIFTGATE - ADJUSTMENTS) for detailed instructions.

If a problem exists with the power liftgate and it is suspected to be extreme effort, check the liftgate prop rods and hinges for free movement. Use a known good vehicle for liftgate effort comparison.

MANUAL RELEASE OF AN INOPERATIVE POWER LIFTGATE LATCH

NOTE: The liftgate may be opened manually by raising the latch release lever in the event the power liftgate latch assembly becomes inoperative. If the latch assembly becomes stuck during a cinch command the cinch function may be overridden by raising the cinch override lever.


1. Remove the access door from the middle of the lower liftgate trim panel.
2. Working through the lower trim panel opening, locate the release lever and pull upward to release the power liftgate latch.

POWER LIFTGATE LATCH HOMING

Following every cinch or release sequence, the power liftgate latch will return to a “home” or neutral position. If for some reason the latch is unable to return to the “home” position, the power liftgate control module will recognize this and prevent the latch from releasing. If this condition exists, activation of the power liftgate feature or exterior handle will result in a short beep from the power liftgate chime.

In this situation, perform the following:


1. Using the scan tool, perform the "Latch Home Position Test"
2. If the "Latch Home Position Test" is unsuccessful, disconnect the battery for 60 seconds. Reconnect the battery and grab the outside handle switch and hold it for at least 20 seconds
3. If the latch still will not release, use the scan tool and select "Actuates", "Latch Motor Release Direction". This will drive the motor longer than just using the outside handle switch
4. If driving the latch by the "Latch Motor Release Direction" worked, perform the "Latch Home Position Test" before returning the vehicle back to the owner. If driving the latch by the "Latch Motor Release Direction" did not work, use the following procedure to open the liftgate and continue diagnosis as necessary. (Refer to 8 - ELECTRICAL/POWER DOORS - STANDARD PROCEDURE - MANUAL LATCH RELEASE) to open the liftgate

POWER LIFTGATE LEARN CYCLE

Any time a power liftgate component is removed, replaced or a liftgate adjustment is performed, a learn cycle must be performed. This learn cycle enables the power liftgate control module to learn or relearn information (travel limits, resistance to door travel, etc.) which allows it to perform properly and safely. To perform a learn cycle do the following:


1. Obtain an appropriate scan tool.
2. Connect the scan tool to the vehicle and check for any power liftgate system stored trouble codes, correct and erase any stored codes.
3. Close liftgate.
4. Using the scan tool, select the Power Liftgate Module (PLGM) Menu, More Options, System Tests and select the Open Door Test.
5. Using a scan tool check “routine status” for a pass or fail message. If the Open Door Test did not pass, the scan tool will display the reason to aid in system diagnosis or rerunning the Open Door Test routine.
6. Using the scan tool, select Power Liftgate Module (PLGM) Menu, More Options, System Tests and select the Close Door Test.
7. Using a scan tool check “routine status” for a pass or fail message. If the Close Door Test did not pass, the scan tool will display the reason to aid in system diagnosis or rerunning the Close Door Test routine.
8. Follow the instructions on the scan tool to complete the test.
9. The liftgate learn cycle is complete.

NOTE: If the power liftgate will not complete a full cycle a problem exists with the power liftgate system.

In order to obtain conclusive testing of the power liftgate system, the Controller Area Network (CAN) data bus, and all of the electronic modules that provide inputs to, or receive outputs from the power liftgate system components must be checked. Any diagnosis of the power liftgate system should begin with, the use of a scan tool and the appropriate diagnostic service information.