What was found
CLIMBING THROUGH 17,000 FT, X'S APPEARED IN CAPTAINS PFD ON AIRSPEED & ALTIMETER TAPES, ADC1 FAIL MESSAGE APPEARED ON FMS SCRATCH PAD, FADEC FAIL L-R, MESSAGE APPEARED ON EICAS. FADECS WOULD NOT RESET. 10-29-07 TESTED, DID NOT CONFIRM. CHECKED FAULT HISTORY IN IMT. SAW SEVERAL ADC INVALID ERRORS LOGGED ON 10/5/07. CHECKED ADC BREAKER WHEN PULLED BREAKER DID NOT MAKE NORMAL "CLICK" SOUND WHEN PULLED. HEAD EXTENDED BEYOND NORMAL, & HEAD SPUN. BREAKER INTERNALLY BAD. REPLACED BREAKER. OPS CHECK GOOD IAW 34-11-07 OF MM.