Service difficulty report · Decoder · Boeing 7379

Difficulty date
June 18, 2021
Submitted
June 18, 2021
Operation
Air carrier
Aircraft
N37506
Make and model
Boeing 7379
Aircraft serial
43432
Aircraft time
3,215 hours, 1,198 cycles
Part
Decoder
Condition
Miswired
Location
Selcal
Stage of operation
CR
How discovered
O
Nature of condition
J
Precautionary procedure
A

As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.

What was found

UPON ESTABLISHING COM W/ AIRINC N NOTIFYING SELCA L INOP BUT EST ABLISHING COM/ AIRINC INITIATED INFO FLAGGING SDR FOR AIR RETURN FOR MASTER CAUTION LIGHTS ON UP ON ESTABLISHING COM W/ AIRINC ALL LIGHT WENT TO NORMAL BUT FAIL OPERATION CHECK NO CALL LIGHT ON ALL 3 AUDIO PANELS. REMOVRD AND REPLACED SELCAL DECODER PER TASK 23-28-11-420-801 DECODER, SELCAL OFF 99-2321-9-0001 8749 ON 99-2321-9-0001 0235 REF LP 6486794 FOUND OBSERVER AUDIO CONTROL PANEL WIRES SWAPPED FOR HF 1-2 CALL LIGHTS. CORRECTED WIRING REF WDM 23-22-11 PER WDM 23-22-11-2.1 AND SSM 23-22-11-101.1 AND EA 2351-01106 CHECKED WIRING OF SELCAL SWITCH THROUGH SELCAL DECODER RACK. NO FAULTS. CHECKED POWER GOING TO SELCAL DECODER WAS GOOD. SELCAL AURAL RELAY CHECKED GOOD. DO FURTHER DISCREPENCIES FOUND ON AUDIO CONTROL PANELS. AFTER RESETING AND RE RACKING SELCAL AIRINC SATISFACTORY WITH CHIME AND LIGHTS ON ALL SYSTEMS. AS HF 1 AND HF2 ALL OPS CHECKED GOOD. COMMUNICATION TO SFO SYSTEM PERFORMED SELCAL CHECKS ON VHF 1, VHF 2 AND VHF 3 AS WELL

More about the Boeing 737-9