# SDR 97ZZZX575

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: January 22, 1997
- Submitted: March 26, 2000
- Operation: General aviation
- Filed by: [HRD Aero Systems Inc, repair station YN2R325L](https://openairdocs.org/faa-repair-station/YN2R325L/hrd-aero-systems-inc.md) (OpenAirDocs)
- Make and model: Doug DC-8
- Registry model: [Doug DC-8](https://openairdocs.org/model/douglas-dc-8) (OpenAirDocs)
- System (JASC): [2621 · Fire Bottle, Fixed](https://openairdocs.org/jasc/2621)
- Part: Switch Gauge
- Part number: 246875
- Condition: Shorted
- Location: Fire Extinguishe
- Component: 899827
- Stage of operation: IN
- Nature of condition: O
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/97ZZZX575

## Discrepancy

SWITCH GAUGE ON FIRE EXTINGUISHER BOTTLE HAS INTERNAL SHORT.  SHORT IS NOT DETECTABLE BY SWITCH GAUGE CHECK PROCEDURE IN FIRE EXTINGUISHER OVERHAUL MANUAL.  TO DETECT A DEFECTIVE SWITCH GAUGE, CHECK PINS 1, 2, AND 3 FOR CONTINUITY WITH THE GAUGE CASE.  IF ANY PIN HAS CONTINUITY WITH GAUGE CASE, SWITCH GAUGE IS DEFECTIVE.

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