What was found
(CAN) INTERMITTENT TCS ADVISORY (AMBER) POSTED ON PILOTS FLIGHT DIRECTOR DURING PREFLIGHT INSPECTION. FOUND BOLT (P/N NAS6203-40, ATA 27-11-01) HAD PENETRATED WIRING HARNESS TO THE PILOTS BUTTON AND SWITCH CONTROLS IN THE STEERING YOKE. SPECIFICALLY THE TCS BUTTON (TOUCH CONTROL STEEING, ATA 22-11-05). ON REMOVAL OF THE HARNESS FROM THE COLUMN, IT WAS FOUND THAT ONE ADDITIONAL WIRE HAD BEEN DAMAGED. IN BOTH CASES THE INSULATION HAD BEEN STRIPPED OFF ABOUT 1/4.