What was found
PILOT'S LEFT HAND STATIC HEATER FAILED, NO ANNUNCIATION WAS OBSERVED. REPLACED DEFECTIVE STATIC PART. AFTER SEVERAL HOURS OF TROUBLESHOOTING AND SEVERAL PHONE CALLS TO CESSNA TO FIND OUT WHY THERE WAS NO FAIL ANNUNCIATION, IT WAS DETERMINED THE SYSTEM WAS OPERATING AS DESIGNED. CONTRARY TO APPROVED MANUALS, THE PITOT/STATIC HEATER FAIL LIGHT WILL ONLY ILLUMINATE WITH A PITOT TUBE HEATER FAIL. STATIC HEATER FAIL, EITHER ONE OR BOTH, WILL NOT SHOW ON THE ANNUNCIATOR PANEL. THE SYSTEM SHOULD WORK AS AN INDICATOR OF A FAILURE OF ANY ONE OF THE THREE HEATING ELEMENTS.