# SDR CALA2024053001627

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: May 24, 2024
- Submitted: May 30, 2024
- Operation: Air carrier
- Aircraft: [N66893](https://openairdocs.org/aircraft/N66893), registered now
- Make and model: Boeing 737924ER
- Aircraft serial: 42197
- Aircraft time: 27,259 hours, 9,905 cycles
- System (JASC): [4990 · APU Oil System](https://openairdocs.org/jasc/4990)
- Part: Pressure Switch
- Part number: 38762552
- Condition: Malfunctioned
- Location: Apu Oil
- Stage of operation: NR
- 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/CALA2024053001627

## Discrepancy

APU COLD SOAK START IS REQUIRED PER ETOPS MANUAL 03-01-09. PLEAS E CONDUCT AN INFLIGHT START AFTER BEING AT CRUISE FOR A MINIMUM OF 2 HOURS. IF SUCESSFUL, SEND MRM CODE UAL4927X, X= NUMBER OF S TART ATTEMPTS, AND FLT LVL AT WHICH START WAS ACCOMPLISHED NONE REF LP 8066831.  TEST FAIL. COLD SOAK. APU LOW OIL PRESSURE LIGHT ILLUMINATED. ETOPS VERIFI CATION FLIGHT REQUIRED AFTER REPAIR. FL 340 FLT 1944 DATE 24MAY24 DEP ORD ARR PHX RESULT U FLT LVL ''''UPON CLEARING THIS MEL ITEM, CONTACT TOMC FOR ASSIGNMENT OF MEL CARD 49001 OR 49003 TO ACCOMPLISH APU ETOPS VERIFICATION ADDITIONAL INFO FROM CREW AFTER THE INITIAL WRITE UP "WE ONLY TRIED IT ONE TIME INSTEAD OF THREE TIMES BECAUSE OF THE LOW FAILED VERIFICATION TEST. LOP COMPLIED WITH MEL FLIGHT.'''' PRESSURE LIGHT" DISPATCH DESK: 90 NAME: AS DATE: 24-MAY-24- NOC DESK: 739 NAME: MF DATE: 24-MAY-24- TOMC APPROVES MEL 4901A. REPLACED LOP PER AMM 49-94-22. MAG CHIP CLEAR, AFTER CHANGE NO CURRENT FAULTS WITH APU RUNNING PARTS USED: 29-4994-3-0001,QTY :1 00-0586-3-1342,QTY :1

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