2006 XK8 with 128,380 miles. No OBDII codes present per my two scanners (one a generic Harbor Freight CenTech, one an iCarsoft i930)....

Went out this morning to do my weekly 25-mile jaunt in my wife's XK8 to keep it happy and healthy. Noticed a very faint but constant ticking sound coming from the right rear quarter panel (this was before getting into the vehicle so the key was still in my pocket). Decided to start the engine and go ahead with my 25-mile jaunt to see if the ticking would disappear afterwards. The car drove normally with no issues. Upon returning home I shut off the ignition, removed the key, got out of the car, and walked back to the rear quarter panel. The constant faint ticking was still present. I opened the trunk lid and leaned in to listen. It sounded as if the noise was coming from the right rear taillight assembly. I removed the interior taillight assembly's plastic cover and then unplugged the taillight assembly's electrical connector. The constant faint ticking continued...

We all know how sounds can seem to be emanating from one area when they are actually coming from a different area. What other components in that general area could be the source of this constant faint ticking sound? Could the long-dormant CD changer be the culprit? As far as I know, that device has not been utilized since we acquired the car in February 2012....

Any suggestions of what this might be and what steps to take in order to resolve it are much appreciated....

 

only thing I could think of from the right side is maybe one of the relays chattering?? Possible low battery voltage causing this or relay itself going bad