syuuritantousya no okage de, kosyoukasyo ga wakarimasita.

おかげで means something like thanks to, because of, or due to in a positive sense.

So 修理担当者のおかげで means thanks to the repair person / technician.

The important nuance is that the speaker is expressing appreciation or a favorable result. It sounds more positive than a neutral 〜で or 〜によって.

For example:

• 先生のおかげで、合格できました。
  Thanks to my teacher, I was able to pass.

If the result were negative, おかげで usually would not be appropriate in normal careful speech. Japanese sometimes uses it sarcastically, but that depends on context.

The の links 修理担当者 and おかげ, showing that the favor/help is associated with that person.

So:

• 修理担当者 = repair person / technician / person in charge of repairs
• おかげ = benefit, help, good effect
• 修理担当者のおかげ = the repair person’s help / thanks to the repair person

This is a very common pattern:

• 友達のおかげで = thanks to my friend
• 先生のおかげで = thanks to the teacher
• あなたのおかげで = thanks to you

In the pattern 〜のおかげで, the で marks the cause or reason that led to the result.

So the structure is:

• Aのおかげで、B
• Thanks to A, B happened

In this sentence:

• 修理担当者のおかげで = thanks to the repair person
• 故障箇所が分かりました = we found out / understood the faulty part

Together: Thanks to the repair person, the faulty part became clear.

You should learn おかげで as a set phrase.

This is a very common learner question.

分かる usually takes が, not を, because it means to be understood, to become clear, or to be known rather than to understand in the direct transitive sense.

So:

• 故障箇所が分かりました = the faulty part became clear / was identified
• not 故障箇所を分かりました

Japanese often expresses this idea as something becoming clear, rather than a person actively understanding something the way English does.

Other examples:

• 意味が分かりました。 = I understood the meaning.
• 答えが分かりません。 = I don’t know the answer. / The answer isn’t clear to me.

They are different verbs.

• 分かる = to understand, to become clear
• 知る = to learn, to come to know, to find out for the first time

In this sentence, 分かりました fits better because the meaning is that the location/part where the malfunction was became clear.

• 故障箇所が分かりました = we now know which part is faulty / the faulty part has been identified

If you used 知りました, it would sound more like I learned about it, rather than it became clear. That is usually less natural here.

故障箇所 is a compound noun:

• 故障 = breakdown, malfunction, failure
• 箇所 = spot, place, location, part

So 故障箇所 means:

• the faulty part
• the location of the malfunction
• the part where the breakdown occurred

It is a technical or practical expression, often used for machines, devices, equipment, cars, appliances, and similar things.

修理担当者 is also a compound noun:

• 修理 = repair
• 担当 = being in charge of, 담당
• 者 = person

So 修理担当者 means:

• the person in charge of repairs
• the repair staff member
• the technician responsible for the repair

Depending on context, English translations could vary a little.

Japanese past tense often describes a change of state that has now been completed.

So 分かりました does not necessarily mean only understood in the past. It often means:

• it became clear
• I found out
• I now understand

In this sentence, the idea is that after the repair person’s help, the speaker reached the point where the faulty part was identified.

So the past tense marks the completion of that discovery.

Yes. Japanese often leaves the subject unstated when it is obvious from context.

The sentence does not explicitly say who came to know the faulty part. Depending on context, it could mean:

• I found out the faulty part
• we found out the faulty part
• it became clear what the faulty part was

Japanese focuses more on the event/result itself than on explicitly stating the subject every time.

A natural reading is:

しゅうりたんとうしゃ の おかげで、こしょうかしょ が わかりました。

Word by word:

• 修理担当者 → しゅうりたんとうしゃ
• おかげで → おかげで
• 故障箇所 → こしょうかしょ
• 分かりました → わかりました

Yes. A more literal translation would be:

Thanks to the repair person, the malfunction location became clear.

That sounds a bit unnatural in English, so a smoother translation would be something like:

• Thanks to the technician, we figured out which part was faulty.
• Thanks to the repair person, the faulty part was identified.
• Thanks to the technician, we found the source of the malfunction.

This is a good example of how natural English often uses an active expression, while Japanese uses X が分かる to express that something became clear.