ACARS inopérant — MU Fail (Management Unit) ou DU Fail (Display Unit dédié).ACARS inoperative — MU Fail (Management Unit) or DU Fail (dedicated Display Unit).
ObjectifObjective
Choisir le bon reset CB (MU ~10 s vs DU ~60 s) et relier au MEL 23-09 / fuel schemes.Choose the correct CB reset (MU ~10 s vs DU ~60 s) and tie to MEL 23-09 / fuel schemes.
MU vs DU — DÉFINITIONS
MU = Management Unit — cœur traitement ACARS/CMU.MU = Management Unit — ACARS/CMU processing core.
DU = Display Unit dédié ACARS — pas l’affichage ACARS via FMS CDU.DU = dedicated ACARS Display Unit — not ACARS display via FMS CDU.
MU FAIL
Message ACARS MU FAIL ou texte aléatoire à l’écran.ACARS MU FAIL message or random text on screen.
Action teaching : pull CB MU environ 10 secondes pour power-down / reset.Teaching action: pull MU CB about 10 seconds for power-down / reset.
DU FAIL
Écran blank : vérifier luminosité ; CB DU non poppé.Blank screen: check brightness; DU CB not popped.
Touch unresponsive : écran sale ou humide ? Pull CB DU ~60 s pour cool / décharge static.Touch unresponsive: dirty or wet screen? Pull DU CB ~60 s to cool / discharge static.
Temps de reset — ne pas inverser MU/DU.Reset times — do not swap MU/DU.
Symptom
Check first
CB action
MU FAIL / random text
—
MU CB ~10 s
DU blank
Brightness · DU CB status
as needed
Touch dead
Dirty / wet screen?
DU CB ~60 s
DISPATCH · FUEL SCHEMES
On GNDMEL 23-09 [ACARS System]
Schemes Flight Monitoring / Flight Watch exigent un moyen fonctionnel de parler à la compagnie.Flight Monitoring / Flight Watch schemes need a functional means to talk to company.
ACARS et SATCOM unavailable → basculer fuel planning en Flight Following (pas Monitoring/Watch).Both ACARS and SATCOM unavailable → fuel planning must use Flight Following (not Monitoring/Watch).
POINTS CLÉSKEY POINTS
DU Fail ≠ CDU FMS — seulement display ACARS dédié.DU Fail ≠ FMS CDU — dedicated ACARS display only.
10 s (MU) vs 60 s (DU touch) — mémoriser la différence.10 s (MU) vs 60 s (DU touch) — memorize the difference.
MEL 23-09 au sol ; fuel scheme Monitoring/Watch exigent comm compagnie.MEL 23-09 on ground; Monitoring/Watch fuel schemes require company comm.
Après reset CB, re-vérifier LINK STATUS (NO COMM page) avant de conclure MU mort.After CB reset, re-check LINK STATUS (NO COMM page) before concluding MU is dead.
Si MU/DU restent morts après reset → traiter comme ACARS System MEL 23-09 et revoir fuel scheme (Following si SATCOM aussi out).If MU/DU stay dead after reset → treat as ACARS System MEL 23-09 and revisit fuel scheme (Following if SATCOM also out).