I recently got the dreaded "air suspension inactive" warning. Turns out the arm on the rear left sensor was broken. Replaced it with an aftermarket sensor, calibrated the air suspension and cleared the fault ("81 - RL height sensor invalid activity"). Everything seemed fine until I it the motorway. The car lowered itself to the motorway height (-20mm) and shortly after I got the same error again (invalid activity). Cleared the fault and drove on - after a few miles the same thing again which made me think it had something to do with the motorway height.
Out of curiosity I cleared the fault and locked the suspension. No errors but when I was on the motorway again I got the error once more after a minute of driving - even though the suspension was locked! It somehow seems to be a speed related issue? any ideas what to do?

Still dealing with the issue...
IIDtool also shows 8A - air suspension CAN error (in the ABS ECU). Also sometimes the suspension goes into hard fault and additionally shows rear right height sensor error. Interestingly when I clear the faults in the EAS computer it clears only one code (but shows 2) and after that no codes are shown. Rear right error only comes on when rear left gave an error first.

What to do next? Replace new height sensor again? BCM? Any ideas what to check or should I go to a stealer and have them read the codes?

when you were on the motorway the suspension lowers around 65mph..this action seems to have triggered your problem...check connections/plugs for broken wires or corrosion.. ... - .- -.




Y. O. L. O.
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Will do. what puzzles me is that the error seems to be connected to the motorway speed and not the actual height (I get the error regardless of motorway setting - tried -20mm and 0mm drop as well as locked suspension). I was under the impression that the sensor only sends a height signal and speed is determined through the ABS sensors?

Did you solve the problems

yes, I switched the sensors from one side to the other and recalibrated everything. Worked fine after that.