SDR ASAA2015071812521

Service difficulty report · Light · Boeing 737490

Difficulty date: July 18, 2015
Submitted: July 22, 2015
Operation: Air carrier
Aircraft: N793AS
Make and model: Boeing 737490
Aircraft serial: 28888
Aircraft time: 54,646 hours, 30,900 cycles
System (JASC): 2210 · Autopilot System
Part: Light
Condition: Inoperative
Location: Nav
Part time: 46,458 hours, 26,953 cycles
Stage of operation: NR
How discovered: 9
Nature of condition: O
Precautionary procedure: O

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

What was found

V NAV LIGHT DOES NOT LIGHT UP. ACFT GROUNDED. DFCS LIBRARY TEST NR 50 SHOWED ALL MCP SWITCH LIGHTS TO BE INOPERATIVE. SUSPECT INTERNAL MCP FAULT. R & R AND TESTED DFCS MODE CONTROL PANEL IAW MM 22-11-34-004-004, MM 22-11-34-404-003. PERFORMED DFCS GROUP NR 10, CURRENT STATUS, NR 15, ALTITUDE ALERT AND NR 32, MCP LRU INTERFACE, TESTS IAW MM 22-11-34-745-001 AND HGS SENSOR TEST FOR FCC IAW HGS SMM 34-36-00. ALL TESTS PASS. ACFT REMAINS QUALIFIED FOR CAT IIIA AUTOLAND AND HGS OPS AND STATUS PLACARD.