When my A321 powers up, the lower ECAM DU shows only a diagonal white line. What does it mean and what would be the fix?

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    $\begingroup$ You have a 321, but lost the POH? And don't have a service contract? $\endgroup$ – abelenky Feb 16 at 18:37
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    $\begingroup$ I'm not sure why people are voting this question down: it's clear and presumably there's some sort of answer to it. Saying that "you should be able to answer this yourself" isn't particularly helpful. As for the 'don't trust what strangers on the internet say' comment, that's perfectly true but you could say the same thing about every question on this site :-) $\endgroup$ – Pondlife Feb 16 at 23:00
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    $\begingroup$ I never could understand why people downvote a question when the OP has a rep of 1. It seems kinda pointless, sort of in the same vein as beating a dead horse. $\endgroup$ – BillDOe Feb 16 at 23:59
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    $\begingroup$ @pondlife The problem with Stack Exchange engaging with this sort of maintenance question is that it's a safety issue. There will be an approved procedure documented for this particular aircraft that might differ from an apparently very similar aircraft operated by another airline. Getting it wrong could be seriously damaging to the health of hundreds of people. I wouldn't want to fly with an airline whose principle source of maintenance information is 'some bloke on the internet'. $\endgroup$ – Redd Herring Feb 17 at 2:41
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    $\begingroup$ The question likely comes from someone using a serious game simulator, it seems such questions are downvoted and closed with a vengeance by some of us. So just ignore them and upvote... $\endgroup$ – mins Feb 17 at 14:46

Display Management Computer issue:

If a DMC fails, all information is removed from the displays it controls and replaced by a white diagonal line to indicate a working display with a failed source. ECAM will detect the failure and provide a sequence of alerts.

Due to the priority rules, the E/WD display will move to the lower DU if it was DMC1 that failed. The EIS DMC switch is used to replace the failed DMC with DMC3.


Steps to clear warning:

First select DMC #3 to isolate fault to DU or DMC. If DMC is at fault reset above associated circuit breaker for 5 seconds. If fault is with DU reset these (CAPT PFD/ND = G3/E1) (FO's PFD/ND = R3/R4) (Upper ECAM = E5) (Lower ECAM = R11).


More in the maintenance manual at AMM31-60-00-710-001. (EIS start).


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