disco 2 air suspension problem ??

Hi , ive not long had my v8 disco 2,and ive got the rear suspension drop , its only the drivers side.it was fine when i went to work in the morning but whem i came back to it after i finished work it had dropped,ive run the car and it wont cum up,so im guessing its the air bag,
but
shouldnt it come up if i press the switch on the dash,well it doesnt and neither does the passengers air bag either ?,also should you here the pump working as mine makes no noise so does this mean the pumps gone, but if the pump had gone wouldnt it have dropped the passengers side aswell,
if it is the pump and an air bag i might aswell convert it to springs as this is an easy and cheap fix and will get rid of any future problems,

Maybe something has frozen up in this cold weather!! There are a number of components that may have failed. Each rear wheel has a "height sensor", the one on the drivers side may have failed. The air pump assembly (under the N/S chassis, midway) has the pump and numerous valves and sensors. Although an airbag leak is not uncommon, after 50k or so, it is unusual for it to fail to re-inflate, after engine running for a few minutes. From what you describe, it sound like your pump is not running, or a valve is stuck. You should be able to hear the pump running. I would advise having a check done with a "diagnostic computer". This is likely to cost around £50 at a main dealer, but may save you in the long run, in pinpointing what has failed.
BTW I have replaced my airbags with vehicle on my driveway. They are available for around £80 each, shopping around. Not too difficult to do if you have a decent trolley jack and axle stands.
Dave
Edinburgh