I'm after a bit of advice, I have just change the lower arms on my 2004 Range Rover and after fitting the air suspension inactive was displayed on the dash. I got the car plugged in and it turns out that it is the front left height sensor. I only had this part replaced whilst on Holiday back in October so it not that old it looks intact is there anything I should check before I get this part replaced as it is not that old or do they have a short life.
My next question would be is it best to get a genuine part or after market what has been found to be best value for money.

Have you tried starting vehicle and turning wheel full lock right to left and see it the fault disappears? first before spending money .
As for sensors I found genuine best, aftermarket sensors failed on mine early.

Thanks for your reply. I have tried lock to lock but didn't work this time thanks for the advice about genuine parts might be why it failed so soon.