SDR ASAA2015080512744

Service difficulty report · Gcu · Boeing 737490

Difficulty date: August 5, 2015
Submitted: August 10, 2015
Operation: Air carrier
Aircraft: N569AS
Make and model: Boeing 737490
Aircraft serial: 35184
Aircraft time: 32,124 hours, 9,993 cycles
System (JASC): 2421 · AC Generator-Alternator
Part: Gcu
Condition: Failed
Location: Apu
Part time: 32,142 hours, 10,000 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

WITH APU RUNNING, NO VOLTS OR FREQUENCIES, APU WILL NOT GO ONLINE. ACFT GROUNDED. REMOVED AND RE-INSTALLED APU GCU IAW MM 24-21-81-400-801. FOUND S16 BAD, R & R APU REMOTE CONTROL PANEL IAW MM 26-22-03-400-801. ACCOMPLISHED APU FIRE EXTINGUISHING BOTTLE SQUIB CIRCUIT TEST, OPS NORMAL REF MM 26-22-00-730-801. ACCOMPLISHED APU GCU INSTALLATION TEST AND APU FIRE SWITCH SYS SHUTDOWN TEST, REF MM 24-21-81, AND MM 26-22-00. ALL OPS NORMAL. APU OPS TEST NORMAL, REF MM 49-11-00.