# SDR ASAA2017040620383

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: April 6, 2017
- Submitted: April 10, 2017
- Operation: Air carrier
- Aircraft: [N478AS](https://openairdocs.org/aircraft/N478AS), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 44105
- Aircraft time: 7,156 hours, 2,384 cycles
- System (JASC): [2150 · Cabin Cooling System](https://openairdocs.org/jasc/2150)
- Part: Warning Light
- Condition: False Activation
- Location: Lt A/C Pack
- Stage of operation: TX
- How discovered: V
- Nature of condition: J
- Precautionary procedure: D
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2017040620383

## Discrepancy

AFTER BOTH ENGINES STARTED, LEFT PACK LIGHT ILLUMINATED. FOLLOWED QRH PROCEDURE AND THE PACK LIGHT WENT OUT FOR A FEW SECONDS, THEN CAME BACK ON AGAIN AND COULD NOT EXTINGUISH THE PACK LIGHT. THE PACK TEMPERATURE SHOWS OVERHEAT.  ACFT GROUNDED.  REVERSED IAW AMM 21-00-00-440-801. ACCOMPLISHED BITE CK OF PACK/ ZONE TEMP CONTROLLERS IAW AMM 21-61-00-700-806-002. WITH & WITHOUT BLEED AIR, BITE CK WAS GOOD WITH NO FAULTS. GROUND VERIFICATION SUCCESSFUL. NO LIGHTS ILLUMINATE ON RECALL.

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