# SDR ASAA2020080642989

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: August 4, 2020
- Submitted: August 6, 2020
- Operation: Air carrier
- Aircraft: [N481AS](https://openairdocs.org/aircraft/N481AS), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 44106
- Aircraft time: 19,151 hours, 6,135 cycles
- System (JASC): [3040 · Windshield/Door Rain/Ice Removal](https://openairdocs.org/jasc/3040)
- Part: Warning Light
- Condition: False Activation
- Location: Lt Window Heat
- Stage of operation: DE
- How discovered: O
- Nature of condition: N
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2020080642989

## Discrepancy

LEFT SIDE WINDOW OVERHEAT LIGHT ILLUMINATED ON DESCENT INTO SEATTLE. GROUNDED - YES. WHCU BIT VERIFY TEST PASS, SENSOR FAULT FOR PREVIOUS LEG. OBSERVED SPARE SENSOR IN USE. RESISTANCE CKS WITHIN LIMITS & SAME VALUE FOR BOTH SENSOR, HEAT FILM CHECKED NORMAL. SHOOK DOWN COIL CORD DURING OPS CKS, UNABLE TO DUPLICATE FAULT REF B737-900 AMM 30-41-21 & 30-41-00.

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