What was found
ROUTINE MAINT WORK REVEALED THAT A/C HAD BEEN OPERATING WITH A WIRE ROUTING DEVIATING WIRE ROUTING REQUIRED BY SB. ON E1-3 ELECTRONIC SHELF, WIRE W467-025-20 HAD NOT BEEN REROUTED TO D8937J CONNECTOR AS INSTRUCTED BY SB 737-27A1206, FIG 5, FLAGNOTE 9. DETECTED DEFECT AFTER YAW DAMPER SERVO TEST FAILED. AS A RESULT OF THE FAULTY WIRE ROUTING, YAW DAMPER COUPLER ONCE MORE FAILED DURING TESTING. INSP OF E1-3 ELECTRONIC SHELF REVEALED 3 RADIO ALTIMETER INTER FACE WIRES; W011-2014-22R, W011-2015-22B AND W011-8725-24 MISSING. SB FIGURE 20 INTRODUCED THESE WIRES AS A PART OF WIRE CHANGE FOR THE RUDDER SYSTEM IMPROVEMENT SB, RULED BY AD. WITH RADIO ALTIMETER INTERFACE MISSING, RECTIFIED CONDITION.