What was found
PILOT EXPERIENCED LOSS OF YAW DAMPERS NR1, NR2, REENGAGEMENT ATTEMPTS UNSUCCESSFUL. AUTO PILOT DISENGAGED AND COULD NOT BE RESET. IN-OP YAW DAMPER, PILOT WAS ATTEMPTING TO LEVEL AC, NO RESPONSE TO PITCH TRIM CNTRL, SECONDARY PITCH TRIM WAS ACTIVATED W/NEGATIVE RESULTS. CHK LIST PROCEDURES FOR PITCH TRIM FAIL, ATC NOTIFIED, DIFFICULTY IN MAINTAINING PITCH CNTRL. AC LANDED SAFELY. FOUND NO PROBLEMS W/PITCH TRIM SYS. FOUND INTERMITTENT SHORT INTERNALLY VIA LOOSE INTERNAL CONNECTIONS. FOUND BY (TAPPING) CNTRL WHEEL WHICH RECREATED FAILURE. INTERNAL SHORT CREATED PERMANENT NR1 AND NR 2 PITCH TRIM DISCONNECT, AC DIFFICULT TO MANEUVER IN PITCH AXIS. WHEEL MASTER SWITCH WAS REPLACED, AC RETURNED TO SERVICE.