For me, it sounds like an old hard-drive that's about to fail. Comes from the behind the glove-box. I can hear this noise after I turn off the vehicle and it lingers for about 2-3 minutes. I've noticed this noise ever since my 12v battery crapped out on me once and I. I do have heated seats but it sounds more like it's coming from the passenger side dash. Tazio Nuvolari said: Two possible causes: 1. You say it clicks with A/C on or off but I would still remove and check the cabin air filter behind the glove box to see if it is screwed up or if there are any leaves or twigs--if it has not been changed since.