This is a common failure part on all Mercedes 18 years or older. In almost every case I have seen, it is the low pressure hose that fails. They seem to rot from the inside out! This hose can fail unexpectedly and leave all your power steering fluid on the roadway. It will leave you stranded. If you try to drive any distance without fluid you can damage your pump and possibly your steering box.
Problem & Solution
Common among these chassis:
Inspect your hose for any signs of swelling or cracking and replace immediately (it is the hose that has clamps on it and is easy to replace on most models). On 124 chassis gas cars you will have to get under the car to inspect. Plan to flush the system and install new fluid at the same time.