For the handbrake cable adjustment on a D2 2003/4 it is done from underneath in the transmission tunnel. You will need a crows foot spanner and also a long extension and also a large crows foot spanner with a long extension. Undo the top larger nut half a turn then unscrew the lower sleeve nut until the handbrake is fully on at 3 clicks of the ratchet and then holding the lower sleeved nut from turning tighten the larger upper nut. Ensure the drum brake is correctly adjusted first or it's an abortive exercise. Job done.

The 1998 to 2002 cable adjustments are shown in RAVE.

 

Thank you this clarifies it. What might have caused the handbrake to come loose? Mine is totally loose and the cable seems not broken.