D2 TD5 auto Advice please - o/s rear drops overnight. Live data reports air pump active at ~ 1-2 second intervals; constant hissing just audible from air pump area. Have sprayed soap solution everywhere, inc air bags - no sign of bubbles. Left car overnight in downhill mode, with back of car raised - no hissing & stayed in raised position.

 

On of the check valves or solenoids has failed, or one of the connections and lines if you are hearing it escape. Or since it held aiming down hill, maybe a height sensor has failed?



I’d be looking at 12, 13,14, or 6.

 

Does suspension deflates on both sides, or left or right only ? Check the hoses/valves pertinent to that side.

 

Just adding my lack of knowledge about air bags from reading other forums over the years…
After you correct your droopy suspension airbag issue, you’ll have to recalibrate the SLS system with a Nanocom to correctly set the ride height.