Cadillac Repair: service air bag, professional facility, climate control

Question
Recently my 2004 deville has a service air bag message and the air bag idiot light stays on. Also there is a loud clicking sound at various speeds that sounds like it's coming from the climate control center. It stops after about a minute. Can you tell me what the problem is and likely repair, expense, etc?

Answer
Do NOT make any attempts to make an air bag repair unless you have the required knowledge to do so as ONE mistake can get you KILLED due to the velocity at which the air bag deploys should you make an OOOPPPSSS !!!.

Have a professional facility make this DANGEROUS repair.