Loss of ADC1 Data and/or ADC2 Data and/or WOW signal on Engine 2

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1. Possible Causes
2 Job Set-up Information
A. Referenced Information
REFERENCE DESIGNATION
73-00-00-810-903-A Loss of the Altitude Indication in Channel in Control on Engine 2
73-20-00-810-874-A Loss of the ADIRS1 and ADIRS2 Inputs on Engine 2
73-20-00-810-892-A Loss of the ADIRU1 Data on Engine 2
73-20-00-810-894-A Loss of the ADIRU2 Data on Engine 2
73-25-00-810-919-A Loss of Weight on Wheels Signal on the System 2
Ref. AMM 24-41-00-861-002 Energize the Aircraft Electrical Circuits from the External Power
Ref. AMM 71-00-00-710-018 Discontinued Start, Restart and Shutdown Procedures
Ref. AMM 71-00-00-710-043 Normal Engine Automatic Start Procedure
Ref. AMM 71-00-00-710-047 Normal Engine Manual Start Procedure
3. Fault Confirmation
Subtask 77-00-00-710-271-B
A. Job Set-up
(1) Energize the aircraft electrical circuits
Ref. AMM 24-41-00-861-002 .
(2) On the panel 50VU, release the ENG FADEC GND PWR 2 pushbutton switch.
Subtask 77-00-00-710-272-B
B. Test
(1) On the panel 50VU, push the ENG FADEC GND PWR 2 pushbutton switch and release it again.
NOTE: This action resets the FADEC memory.
(2) Adjust the brightness of the MCDU screen.
(3) Push the INIT mode key. The INIT page comes into view.
(4) Enter a new flight number.
(5) Start the engine 2 by the normal engine automatic start procedure Ref. AMM 71-00-00-710-043 or
the normal engine manual start procedure Ref. AMM 71-00-00-710-047 .
NOTE: Operation of the engine for at least 3 minutes erases the LAST LEG REPORT related to the
last flight and the new fault is recorded in the EEC LAST LEG REPORT.
(6) Do a shutdown of the engine 2 by the discontinued start, restart and shutdown procedure Ref.
AMM 71-00-00-710-018 .
(7) Read the LAST LEG REPORT of the FADEC (2A and 2B) menu on the MCDU (Ref. 70-00-00 Page
Block 301 Task Supporting Data).
(a) Make a record of the maintenance message.
(b) Make a record of the channel FADEC 2A or FADEC 2B which found the fault.
(8) Fully decrease the brightness of the MCDU screen (display off).
4. Fault Isolation
Subtask 77-00-00-810-193-B
A. If the fault symptom is identified by the maintenance message EIU/LGCIU/WOW 2, do the associated
troubleshooting procedure (Ref. TSM 73-25-00-810-919) .
NOTE: This message is only set in flight. Fault confirmation is not applicable.
(1) If the test gives the following maintenance message(s), do the associated troubleshooting
procedure(s):
· ADIRS1/HC/EEC 2 (Ref. TSM 73-20-00-810-892) .
· ADIRS2/HC/EEC 2 (Ref. TSM 73-20-00-810-894) .
· EEC2/ADIRS 1/ADIRS 2 (Ref. TSM 73-00-00-810-903) .
· ADIRS 1/ADIRS 2/EEC 2 (Ref. TSM 73-20-00-810-874) . [Rev.6 from Feb 2017] 2026.04.04 04:37:50 UTC