Hi, new to forum so hello everyone, can anybody tell me how to adjust parking brake on my 1999 ml320, got excess travel. Thanks.

 

First thing you need to check is the Ebrake shoes. they are probably worn very thin or are falling off the backing plate.
You can also remove the rear wheels and adjust the star wheel to tighten or slacken the ebrake, through the lug bolt holes using a small flat head screw driver or appropriate tool. I think also there is an adjustment above the driveshaft under the car..not totally sure if this car has that design or not. But normally adjusting the star wheel will take care of your issue.