The rear fog lamp bulb is replaced as follows:
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Detach the panel on the inside of the tailgate by first turning the two knobs a quarter turn anticlockwise. Then unhook the panel and place it to one side.
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Undo the bulb holder by turning it a quarter turn anticlockwise and pulling it out.
Remove the blown bulb from the bulb holder by pressing it in and turning anticlockwise.
Fit a new bulb by pressing it in and turning it clockwise.
Wipe the bulb's lens clean of any dirt, grease or moisture.
Attach the bulb holder by turning it a quarter turn clockwise.
Refit the panel and lock it on by turning the knobs a quarter turn clockwise.