hwamyeon saegi isanghaeseo dasi kyeossdeoni gwaenchanhajyeosseo.

화면 색 literally means screen color.

• 화면 = screen, display
• 색 = color

In Korean, two nouns are often placed next to each other like this, where the first noun describes the second. So 화면 색 means the color of the screen or the screen’s color.

The 이 is the subject marker.

So:

• 화면 색이 이상해서 = because the screen color was strange

Here, 색이 marks the screen color as the thing being described by 이상하다 (to be strange / odd).

이상해서 comes from 이상하다 (to be strange, weird, odd) plus -아서/-어서, which often means because or so.

So 이상해서 means:

• because it was weird
• since it looked strange

In this sentence, it gives the reason for the next action: the screen color was strange, so the speaker turned it on again.

Both can give a reason, but -아서/-어서 often sounds more natural for a straightforward cause-and-result sequence.

• 이상해서 다시 켰어 = it was weird, so I turned it on again
• 이상하니까 다시 켰어 = since it was weird, I turned it on again

-니까 can sound a little more like the speaker is judging or explaining the reason more explicitly.
-해서 feels very natural in everyday storytelling here.

다시 켰더니 means something like:

• when I turned it on again
• after I turned it on again
• I turned it on again, and then...

It is made of:

• 다시 = again
• 켰더니 = from 켜다 (to turn on) + -었더니

The grammar -더니 / -았더니 / -었더니 often connects a first action or situation to a result that the speaker then noticed.

So here the flow is:

1. The screen color was weird.
2. I turned it on again.
3. Then it became fine.

This is a very common question.

• 켜서 = because I turned it on / turning it on and...
• 켰더니 = when/after I turned it on, I found that...

In this sentence, 켰더니 is better because it emphasizes the result that the speaker discovered afterward.

So:

• 다시 켜서 괜찮아졌어 sounds less natural for this exact meaning
• 다시 켰더니 괜찮아졌어 naturally means I turned it on again, and then it turned out fine

The -더니 form often has a feeling of I did X, and then I saw/realized Y.

Because 켜다 goes into the past form 켰어.

So:

• dictionary form: 켜다 = to turn on
• past stem: 켰-
• plus -더니 gives 켰더니

This is just the normal past formation for 켜다.

The object is omitted because it is obvious from context.

From the sentence, we can infer it is probably:

• the device
• the monitor
• the phone
• the computer
• the TV

Korean often leaves out objects when they are easy to guess.
So 다시 켰더니 really means something like when I turned it back on again.

In natural English, we might say I restarted it even though Korean literally says turned it on again.

Usually, yes, or at least that is strongly implied.

Literally, 다시 켜다 means turn on again, and in real life that usually suggests the speaker:

• turned it off and on again, or
• restarted/rebooted it

Korean does not need to spell out every step if the situation is clear.
So even though 끄고 다시 켰더니 (after turning it off and on again) would be more explicit, 다시 켰더니 is perfectly natural.

This is an important nuance.

• 괜찮았어 = it was okay
• 괜찮아졌어 = it became okay / it got better / it returned to normal

The sentence describes a change of state:

1. something was wrong
2. then after turning it on again
3. it became okay

So 괜찮아졌어 is the natural choice because it shows improvement or recovery.

The subject is omitted, but it refers to the problem situation—most naturally the screen or the screen color.

Depending on how you translate it, it could mean:

• the screen became fine
• the color went back to normal
• it became okay

Korean often leaves out subjects when they are understood from context.

괜찮아졌어 is in the casual, informal speech level.

Compare:

• 괜찮아졌어 = casual
• 괜찮아졌어요 = polite
• 괜찮아졌습니다 = formal

So this sentence sounds like something you would say to:

• a friend
• someone younger
• someone you are close to

Yes, that is a very natural translation.

Even though the Korean literally says turned it on again, in real context English often prefers:

• I restarted it
• I rebooted it
• I turned it off and back on

So that translation captures the intended meaning well.

In general, 이상하다 can mean:

• strange
• weird
• odd
• unusual

In this sentence, it is clearly negative, because the weird screen color is treated as a problem.
So here it means something like:

• the color looked off
• the screen color was weird
• something was wrong with the display color

Yes:

• 화면 색이 = the screen color
• 이상해서 = because it was strange / weird
• 다시 = again
• 켰더니 = when I turned it on again / after I turned it on again
• 괜찮아졌어 = it became okay / it went back to normal

So the full sense is:

The screen color was weird, so I turned it on again, and it went back to normal.