There is a high presure line and a low pressure return line.

Usually the return line(2 pieces) is the ones that leaks. It's sold by the meter at the dealership and a liter of fluid. Not a big deal. You don't need a new $1200 pump unless you run the thing dry.
The front seals go bad and o-rings in the pump. When the pump leaks, there is a kit(from the dealers also) about $15-45 depending on which pump model and manufacture. Takes about an hour off the car.


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