Fault Message:

APU SHUT DOWN - INLET DOOR NOT OPEN

Fault Code:

4960122APU

Associated CAS:

APU SHUTDOWN
(Advisory)

The Full-Authority Digital Engine-Controller (FADEC) commanded an Auxiliary Power Unit (APU) shut down because the inlet door closed during operation.

• Door Actuator (A199)
• Inlet Door Rotary Transducer (MT5)
• Associated Wiring

Advisory Wire/Service Bulletin: None

Forum Articles/Infoservice/Newsletter: None

1. On the CAIMS PMAT, get access to the active faults.

   1. If the fault message FADEC CONTROLLER shows on the CAIMS PMAT, go to step 8.
   2. If the fault message not shows, continue with next step.

2. On the CAIMS PMAT, get access to the active faults.

   1. If the APU SHUTDOWN (Advisory) still shows on the EICAS primary display, go to step 4.
   2. If any of the fault messages that follow show on the CAIMS PMAT, continue with next step.

3. Troubleshoot fault message that follows:

   1. OPEN CKT−INL DOOR RTRY XDCR/EXC
   2. OPEN CKT−INL DOOR XDCR/SEC VA WRG
   3. OPEN CKT−INL DOOR XDCR/SEC VB WRG
   4. SHORT−INL DOOR RTRY XDCR/SEC VA WRG
   5. SHORT−INL DOOR RTRY XDCR/SEC VB WRG

4. Examine the linear actuator (A199) receptacle for contamination and damage.

   1. If there is contamination or damage, repair or replace as required and do close out.
   2. If there is no contamination or damage, continue with next step.

5. Perform a resistance check on actuator connector as follows:

   From	To	Expected Result	Result
   A199P1-A	Ground	>1 megohm
   A199P1-C	Ground	>1 megohm
   A199P1-D	Ground	>1 megohm

   1. If resistance checks good, go to step 9.
   2. If resistance checks not good, continue with next step.

6. Perform a resistance check on connector as follows:

   From	To	Expected Result	Result
   P803-E	Ground	>1 megohm
   P803-F	Ground	>1 megohm

   1. If resistance checks not good, repair or replace defective wiring as required and do close out.
   2. If resistance checks good, continue with next step.

7. Perform a resistance check on connector as follows:

   From	To	Expected Result	Result
   J803-E	Ground	>1 megohm
   J803-F	Ground	>1 megohm

   1. If resistance checks not good, repair or replace defective wiring as required and do close out.
   2. If resistance checks good, continue with next step.

8. Replace APU FADEC.

   1. If system checks are good, do close out.
   2. If fault remains, continue with next step.

9. Replace Linear Actuator (A199).
10. Do close out.