kuruma ga kabe ni sessyokusita.

It is read:

くるま が かべ に せっしょくした。

• 車 = くるま = car
• 壁 = かべ = wall
• 接触した = せっしょくした = made contact / collided / touched

が marks the grammatical subject of the sentence.

So 車が means the car is the thing that did the action or was involved in the event.

In this sentence, the basic structure is:

車が = the car
壁に = with / against the wall
接触した = made contact

You could think of が here as identifying what came into contact.

Here, に marks the target or point of contact.

So 壁に接触した means made contact with the wall.

This can feel a little different from English, because English says contact with something, but Japanese often uses に with verbs like this to show the thing affected or reached.

So:

• 壁に接触した = came into contact with the wall

Because 接触する does not normally treat the thing contacted as a direct object with を in the usual way.

Instead, Japanese typically says:

• Aが Bに 接触する
  = A comes into contact with B

So in this pattern:

• A takes が
• B takes に

That is why 壁に is natural here, not 壁を.

接触した is the past plain form of 接触する.

• 接触 is a noun meaning contact
• する turns that noun into a verb: to make contact / to come into contact
• した is the past form of する

So:

• 接触する = to make contact / to come into contact
• 接触した = made contact / came into contact

This noun + する pattern is very common in Japanese.

Because した is past tense.

• 接触する = makes contact / will make contact
• 接触した = made contact / came into contact

So the sentence is describing an event that already happened.

It is natural, but it sounds fairly formal, technical, or report-like.

For example, it fits well in:

• news reports
• police reports
• insurance descriptions
• written accident summaries

In casual conversation, people might more often say:

• 車が壁にぶつかった。 = The car crashed into the wall.
• 車が壁に当たった。 = The car hit the wall.

Compared with those, 接触した sounds more neutral and less vivid. It can suggest contact without strongly emphasizing a dramatic crash.

The difference is mainly tone and strength.

• 接触した = made contact; somewhat formal, neutral, sometimes lighter or more clinical
• ぶつかった = bumped into / crashed into; more everyday and often more forceful

So if you are describing an accident in a report, 接触した may sound appropriate.
If you are talking casually about a crash, ぶつかった is often more natural.

Japanese normally does not use articles like a or the.

So 車 can mean:

• a car
• the car
• cars

And 壁 can mean:

• a wall
• the wall

The exact meaning depends on context.

So 車が壁に接触した。 could mean:

• A car made contact with a wall.
• The car made contact with the wall.

Context tells you which is intended.

Yes, 車は壁に接触した。 is possible, but the nuance changes.

• 車が壁に接触した。
  This presents the car as the subject of the event. It can sound more neutral or descriptive.

• 車は壁に接触した。
  This makes the car the topic. It can sound like you are talking about the car specifically, perhaps in contrast with something else.

For example:

• 車は壁に接触したが、運転手にけがはなかった。
  = The car hit the wall, but the driver was not injured.

So が is often the more straightforward choice for simply stating what happened.

The order is:

車 / が / 壁 / に / 接触した
car / subject marker / wall / target marker / made contact

Japanese usually places the verb at the end, so this follows a very normal pattern:

[subject] + [location/target/etc.] + [verb]

A natural literal breakdown is:

• 車が = the car
• 壁に = with / against the wall
• 接触した = made contact

Usually, yes.

Because 車 and 壁 are involved, 接触した will often be understood as an accident or collision, even though the verb itself literally just means made contact.

That said, the sentence is fairly neutral. It does not by itself tell you:

• how serious the impact was
• whether anyone was hurt
• whether it was intentional
• whether the damage was large or small

It simply states that the car came into contact with the wall.