03/25/21
Message Overview:
Message Description:
Lighting Detection System data bus (LDS-1) is reported absent by the right PFD, while it is not reported absent by at least 2 of the following: Left PFD, right MFD and left MFD.
CSUs are strapped for LDS Option, (WD-06 Strap 15).
Possible Causes:
- Adaptive Flight-Display Unit 'A429 Input' (R PFD) (A26)
- Junction Box 1 (JB1)
- Associated Wiring
Troubleshooting Tips:
Advisory Wire/Service Bulletin: None
Forum Articles/Infoservice/Newsletter: None
Quick Links:
| Removal of the Junction Box JB1 | AMM 24-63-01-000-802 |
| Installation of the Junction Box JB1 | AMM 24-63-01-400-802 |
| Removal of the Adaptive Flight-Display Unit | AMM 31-61-01-000-801 |
| Installation of the Adaptive Flight-Display Unit | AMM 31-61-01-400-801 |
| Removal of the Lighting Detection Processor | AMM 34-46-01-000-801 |
| Installation of the Lighting Detection Processor | AMM 34-46-01-400-801 |
| Wiring - Maintenance Practices - ALL | SPM 20-12-00-02 |
| Wire Repair - Maintenance Practices - ALL | SPM 20-12-10-02 |
| Electrical Connectors - Maintenance Practices - ALL | SPM 20-20-00-02 |
Troubleshooting Recommendations:
- Reset R PFD Circuit Breaker CB2-C3. Is the fault message still present?
- If NO, do close out.
- If YES, continue with next step.
- Swap R PFD (A26) with R MFD (A28). Is the fault message still present?
- If NO, do close out.
- If YES, continue with next step.
- Do wiring check between R PFD (A26), through JB1, and the other AFDs for the following wires:
From: To: Result: Conn. A26P2 - 86 Conn. A27P2 - 86 Conn. A26P2 - 87 Conn. A27P2 - 87 Conn. A26P2 - 86 Conn. A28P2 - 86 Conn. A26P2 - 87 Conn. A28P2 - 87 Conn. A26P2 - 86 Conn. A29P2 - 86 Conn. A26P2 - 87 Conn. A29P2 - 87 - If the check is not satisfactory, repair defective wiring or replace defective JB1.
- If the check is satisfactory, continue with next step.
- Do close out.