Problems with the airbag rear suspension. Over the years that we've had it, it has had rear suspension airbags replaced a couple of times. Always, the problem has been that overnight, one side would sag. If left long enough, the whole back end would be on its arse. Now, it has decided to do the opposite. With the engine running, the suspension jacks itself up full - in fact maybe more than normal full. You can't seem to make it do anything like the right things from the dashboard switch, although it does chime as it should if the ride height elevation is engaged. The dashboard light seems to be a bit arbitrary as well now. Tonight for instance, although the suspension was fully up, there was no dashboard light on an outbound journey, On the return, the light came on, even though nothing had been touched.
If the car is left for a couple of hours, the nearside seems to go down compared to the offside quite quickly. My buddy has run a scanner over it, and there are a couple of hard faults logged that say that valves in the suspension compressor circuit have exceeded their service life. He thinks that this is something to do with the problem, but I think that it might just be an 'information only' red herring. The scanner would not allow these errors to be cleared.
My feeling is that it is something to do with the nearside going down. Could it be that it has a fairly large leak in that bag or its pneumatic feed circuit,and with the engine and compressor running and the car raised up, that leak is almost beyond the compressor's ability to compensate so it's running all the time confusing the ECU and jacking the suspension right up on both sides ?
I really don't understand the operation of this suspension system well enough to be properly diagnosing this problem, so is there anyone amongst the usual suspects that can offer any pointers please ?
Ta
Arfa