# SDR ASAA2020020532082

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: February 3, 2020
- Submitted: February 6, 2020
- Operation: Air carrier
- Aircraft: [N481AS](https://openairdocs.org/aircraft/N481AS), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 44106
- Aircraft time: 17,826 hours, 5,763 cycles
- System (JASC): [2497 · Electrical Power System Wiring](https://openairdocs.org/jasc/2497)
- Part: Buss Bar
- Part number: BACB29B7S2
- Condition: Loose
- Location: Cockpit
- Stage of operation: IN
- How discovered: V
- Nature of condition: O
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2020020532082

## Discrepancy

DURING TROUBLESHOOTING FOR HOT BATT BUS CB TRIPPING PER TSR704710, FOUND LOOSE BACB29B7S2 BUS ASSY AND EXHIBITED EVIDENCE OF ARCING. GROUNDED - YES. REMOVED LOOSE BUS ASSY AND REMOVED AND REPLACED CIRCUIT BREAKERS C1361 AND C1362 PRECAUTIONARY PER ASA 737 SWPM 20-30-00. A BUNDLE OF WIRE TIES WAS ALSO FOUND IN THE WIRING OF THE P6-2 PANEL AND REMOVED. REINSTALLED AND TESTED BATTERIES PER B737-900 AMM 24-31-11 AND APPLIED POWER. PERFORMED CDS OPERATIONAL TEST PER  AMM 31-62-00-710-801 AND CDS SYSTEM TEST PER AMM 31-62-00-730-801, ENG FIRE EXT SQUIB TEST PER AMM 26-21-02, APU FIRE EXT SQUIB TEST PER AMM 26-22-02, FUELING CONTROL AND SHUTOFF VALVES TEST PER AMM 28-21-00, AND CLOCKS TEST PER AMM 31-25-00 - ALL TESTS PASS.

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