I have a 2001 Mercedes ML320 with 173,000 miles. When I bought it, the parking brake didn't work. I tried looking for videos to fix it, but not many people drive em. When I push the pedal to engage the parking break, it goes down without any resistance. If I try disengaging it, it comes up with no problem. I've looked it up, but there's just to many "might be" in the reasons. Any ideas what could be causing it? And if so, do you recommend taking it somewhere to get it fixed, or can I fix it myself?
Parking brake cables can be a pain in the rear end to fix. If the pedal goes straight down with no resistance, check the connection to the cable inside the car, then get the vehicle up on stands and follow the line from where it comes through the floor/firewall and down underneath the floor. It will go back to the rear and enter an equalizer, which splits it into two separate lines, one for each rear wheel. Look for breaks in the cables or corrosion. Also check where it goes into the rear brake assembly. I'm not sure how the cable connects to a caliper, but the problem should be pretty obvious.
I had this problem with my Ford Ranger a couple years ago. Mine was easy to figure out being a truck cuz I could get under it while all 4 wheels were on the ground. The main cable was fine, but the driver's side one was bad.
