Lincoln navigator suspention light is on???

if you bought it from a dealer take it back chances are they knew the light would be coming on and even thou you bought it without warranty they still can not knowingly lsell a defected car. Threaten to call the loan bank and make a big deal out of it because its expensive to have this system repaired. When the light comes on it means something is wrong even if the air system seems to be working there is some part of it that has failed or is going to fail and once again it cost a lot of money to get it fixed.