# SDR G1IA20230318042

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: March 18, 2023
- Submitted: April 5, 2023
- Operation: Air carrier
- Aircraft: [N771PD](https://openairdocs.org/aircraft/N771PD), registered now
- Make and model: Beech C90A
- Registry model: [Beech C90A](https://openairdocs.org/model/beech-c90a) (OpenAirDocs)
- Aircraft serial: LJ1635
- Aircraft time: 11,902 hours, 16,964 cycles
- System (JASC): [3400 · Navigation System](https://openairdocs.org/jasc/3400)
- Part: Dpu
- Part number: 6229682004
- Part serial: 143CN
- Condition: Abnormal
- Stage of operation: CR
- How discovered: O
- Nature of condition: I
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/G1IA20230318042

## Discrepancy

UPON STARTING ENGINES BOTH EFIS SCREENS EXHIBITED GHOSTING AND ARTIFACTS. AFTER A FEW SECONDS THE NUMBERS OF THE COMPASS CARD DISAPPEARED AND RED BOXES APPEARED IN BOTH SCREENS. REMOVED DPU P/N: 622-4682-004 S/N: 143CN AND INSTALLED DPU P/N: 622-4682-004 S/N: 813. ALL WORK DONE IAW COLLINS EFIS-84 IM P/N: 523-0775965 PAR. 2.7.7.1 F&G PAR. 2.7.7.2 PAR. 2.8.2. FUNCTION CHECKED GOOD. NO DEFECTS NOTED.

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