# SDR ASAA2018072325512

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: July 23, 2018
- Submitted: July 27, 2018
- Operation: Air carrier
- Aircraft: [N493AS](https://openairdocs.org/aircraft/N493AS), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 41727
- Aircraft time: 8,895 hours, 3,023 cycles
- System (JASC): [3040 · Windshield/Door Rain/Ice Removal](https://openairdocs.org/jasc/3040)
- Part: Controller
- Part number: 8300005605
- Part serial: 25246
- Condition: Faulty
- Location: Window Heat
- Part time: 8,963 hours, 3,048 cycles
- 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/ASAA2018072325512

## Discrepancy

L SIDE WINDOW HEAT OVERHEAT LIGHT CAME ON DURING DESCENT AT 9000' TURNED WINDOW HEAT SWITCH OFF. LIGHT WENT OUT. TURNED SWITCH BACK ON. LIGHT STAYED OUT AND WORKED NORMALLY. GROUNDED - YES. PERFORMED BITE TEST ON LEFT SIDE WINDOW HEAT CONTROL UNIT, FAULT HISTORY LOGGED "WINDOW SENSOR" FROM LAST 8 LEGS REF FIM 30-41 TASK 801. ACCOMPLISHED FIM 30-41 TASK 811, TEST PASSED. DUE TO HISTORY AND PRECAUTIONARY, REMOVED & REPLACED LEFT SIDE WHCU AND PERFORMED GOOD INSTALLATION TEST REF AMM 30-41-11.

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