(5) Replace the ADIRU, these are the tasks: Air Data Inertial Reference Unit Removal, AMM TASK 34-21-01-000-801, Air Data Inertial Reference Unit Installation, AMM TASK 34-21-01-400-801.
(a) If you find a problem during the test, then correct the problem and re-run the test. 1) If the test is satisfactory, then you corrected the fault.
-------------------------END OF TASK ---------------------------
840. ADR Data Invalid -Fault Isolation
A. Description
(1)
This task is for this maintenance message:
(a) 34-21007 ADR DATA INVLD
(2)
The maintenance message is identical for the left and right air data inertial reference systems (ADIRS). The left ADIRS maintenance message is shown on the ADIRS L BITE page on the control display unit (CDU). The right ADIRS maintenance message is shown on the ADIRS R BITE page on the CDU.
(3)
Each ADIRU supplies air data reference (ADR) data to many systems and components. ADR data is on ARINC 429 data buses. The data on each ADR bus is the same. One data bus goes from the ADR section of the ADIRU to the IR section.
(4)
The message 34-21007 shows when the IR receives invalid data from the ADR section of the ADIRU. The ADR fault also causes the status code 07 to show on the inertial system display unit (ISDU).
B. Possible Causes
(1)
ADM Sensors
(2)
AOA Sensors
(3)
TAT Probe
(4)
ADIRU, M1749 (left) or M1752 (right)
C. Circuit Breakers
(1) These are the primary circuit breakers related to the fault:
CAPT Electrical System Panel, P18-1
Row Col Number Name
E 5 C01009 ADIRU LEFT DC
E 7 C01007 ADIRU LEFT AC
CAPT Electrical System Panel, P18-2
Row Col Number Name
E 8 C00425 ADIRU LEFT EXC
F/O Electrical System Panel, P6-1
Row Col Number Name
C 14 C01008 ADIRU RIGHT AC
C 15 C00426 ADIRU RIGHT EXC
C 17 C01010 ADIRU RIGHT DC
EFFECTIVITY
34-21 TASKS 839-840
SIL ALL
Page 275 D633A103-SIL Oct 15/2008
D. Related Data
(1)
(SSM 34-21)
(2)
(WDM 34-21)
E. Initial Evaluation
(1)
For
the
applicable
ADIRS,
do
this
task:
ADIRS
BITE
Procedure,
34-21
TASK
801.
(2)
If other maintenance messages show on the CDU along with the maintenance message 34-21007, then do the corrective tasks to remove those maintenance messages first.
(a)
After you clear the correlated faults, if the maintenance message 34-21007 does not show on the CDU, and the status code 07 does not show on the ISDU, then you corrected the fault.
(b)
After you clear the correlated faults, if the maintenance message 34-21007 continues to show on the CDU, and the status code 07 shows on the ISDU, then do the Fault Isolation Procedure below.
F. Fault Isolation Procedure
(1)
Do the air data inertial reference (ADIRS) system self-test in this task: Air Data Inertial Reference System -Operational Test, AMM TASK 34-21-00-710-801.
(a)
If static and/or pitot ADM test is unsatisfactory, then do these steps.
1) Replace the static and/or pitot ADM as appropriate. These are the tasks: Pitot Air Data Module Removal, AMM TASK 34-21-04-000-801 Pitot Air Data Module Installation, AMM TASK 34-21-04-400-801 Static Air Data Module Removal, AMM TASK 34-21-04-000-802 Static Air Data Module Installation, AMM TASK 34-21-04-400-802 a) If pitot and/or static ADM test is satisfactory, then you corrected the fault. b) If the test is unsatisfactory, then continue. 中国航空网 www.aero.cn 航空翻译 www.aviation.cn 本文链接地址：737-600/700/800/900 FAULT ISOLATION MANUAL 故障隔离手册 导航(72)
