Left FMC data bus (L-FMC-2) is reported absent by the left MFD and the left IOC has not received left PFD data.

• Adaptive Flight-Display Unit 'A429 Input' (L MFD) (A29)
• Adaptive Flight-Display Unit 'A429 Input' (L PFD) (A27)
• Junction Box 2 (JB2)
• Left Flight Management Computer (L FMC) (A4-FMC1)
• Integrated-Avionics Processor System (IAPS) Card Cage (ICC) (A4)
• Associated Wiring

Advisory Wire/Service Bulletin: None

Forum Articles/Infoservice/Newsletter: None

1. Confirm all switches on the reversion select panel are selected to NORM.
2. Reset L MFD Circuit Breaker CB1-C5 and L PFD Circuit Breaker CB1-C3. Is the fault message still present?

   1. If NO, do close out.
   2. If YES, continue with next step.

3. Interchange L MFD (A29) with R MFD (A28). Is the fault message still present?

   1. If NO, do close out.
   2. If YES, continue with next step.

4. Interchange L PFD (A27) with R PFD (A26). Is the fault message still present?

   1. If NO, do close out.
   2. If YES, continue with next step.

5. Interchange L FMC (A4-FMC1) with R FMC (A4-FMC2). Is the fault message still present?

   1. If NO, do close out.
   2. If YES, continue with next step.

6. Do wiring check between L MFD (A29), through JB2, and L PFD (A27) for the following wires:

   From:	To:	Result:
   Conn. A29P1 - 35	Conn. A27P1 - 35
   Conn. A29P1 - 36	Conn. A27P1 - 36

   1. If the check is not satisfactory, repair defective wiring or replace defective JB2.
   2. If the check is satisfactory, continue with next step.

7. Do wiring check between L MFD (A29), through JB2, and IAPS Card Cage (ICC) (A4) for the following wires:

   From:	To:	Result:
   Conn. A29P1 - 35	Conn. A4P1 - 26
   Conn. A29P1 - 36	Conn. A4P1 - 27

   1. If the check is not satisfactory, repair defective wiring or replace defective JB2.
   2. If the check is satisfactory, continue with next step.

8. Replace IAPS Card Cage (A4)
9. Do close out.