Buick 2004 Rendezvous Owner's Manual page 405

If the spare tire will not lower, the secondary latch may
be engaged causing the tire not to lower. Do the
following to check the cable:
1. Check under the vehicle to see if the cable is
visible.
2. If it is not visible, see "Secondary Latch System"
following.
If it is visible, first try to tighten the cable by turning
the folding wrench clockwise until you hear two
clicks or feel it skip twice. You cannot over-tighten
the cable.
3. Then loosen the cable by turning the wrench
counterclockwise three or four turns.
4. If the spare tire has not lowered, tighten the cable
all the way and then loosen it at least two times.
If the spare tire did lower to the ground, continue
with Step 5 under "Removing the Spare Tire
(Vehicles with the Rear Convenience Center)"
earlier in this section.
5. If you still cannot lower the spare tire to the ground,
see "Secondary Latch System" following.
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