# SDR CALA2026010912831

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: January 8, 2026
- Submitted: January 9, 2026
- Operation: Air carrier
- Aircraft: [N12221](https://openairdocs.org/aircraft/N12221), registered now
- Make and model: Boeing 737824
- Aircraft serial: 28930
- Aircraft time: 81,112 hours, 30,432 cycles
- System (JASC): [8097 · Engine Starting System Wiring](https://openairdocs.org/jasc/8097)
- Part: Elec Connector
- Part number: MTCPQKT2P22PGCA
- Condition: Damaged
- Location: Zone 400
- Stage of operation: CL
- How discovered: V
- Nature of condition: J
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/CALA2026010912831

## Discrepancy

START VALVE ILUMINATED,  NR 1 ENGINE.   PILOTS REPORT NR 1 ENGINE START VALVE INDICATION SHOWED OPEN AFTER TAKE OFF. ELECTRICAL CONNECTOR PINS & CONTACTS INSPECTED.  NO DAMAGE FOUND. MANUALLY ACTUATED START VALVE & OPS OK.  SLAVED NEW START VALVE & INDICATION STILL SHOWED START VALVE OPEN. CREW REPORTED LEFT ENGINE START VALVE LIGHT ON INFLIGHT ACCOMPANIED BY NO DUCT PRESSURE FROM LT BLEED AS WELL AS THE LT PACK TURNING OFF ACFT HAS HISTORY FOR THE EXACT SAME ISSUES.  AFTER CONNECTOR D39911 WAS REPLACED PROBLEM WENT AWAY FOR ALMOST 2 MONTHS,  INSPECTED CONNECTOR D39911 FOR ANY ISSUES ALSO PERFORM EEC & CDS BITE FOR ANY RELATED FAULTS & LIST ON THIS LOGPAGE AS FAR AS LEFT DUCT GOING TO ZERO. SDS 36-11-00-213, WHEN START VALVE IS OPEN THIS ENERGIZES START CUT OUT RELAY K20 IN THE LT A/CON ACCESSORY UNIT WHICH CLOSES SOLENOID IN BAR. & SHUTS OFF BLEED AIR SUPPLY FROM THE NR 1 ENGINE DURING START. SUSPECT A SHORT TO GROUND ON ENGINE 1 START VALVE OPEN INDICATION CIRCUIT IAW WDM 80-11-11 AND WDM 36-11-11 SUGGEST STARTING WITH CONNECTOR D39911 AS STATED ABOVE, NOTE, LT ACAU & ENGINE 1 START VALVE RAN BOTH ENGINES, START VALVE LIGHTS WENT OFF AND START VALVE WORKED AS INTENDED. ORIGINAL DISCREPANCY CLEARED.

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