The reason for your 2012 dodge avenger's clicking noise largely depends on when and where you hear it coming from. as a '12 avenger owner myself (sxt plus trim here), i've also fallen victim to one of the most common repairs you'll need to make. a failed blend door actuator can cause clicking behind the dash. the reason for this is that there are small plastic gears inside the actuator, which are particularly prone to snapping off. the cogs still attempt to spin, but they just make a loud clicking noise instead. if you don't think this is your issue, you might be hearing something else like lifter noise from your engine, slight engine knocking (which can sometimes sound like a click), or something else altogether.
If the clicking is coming from under the dash, it's either the body control module starting up or a defective actuator on the 2012 dodge avenger.