Кодовый замок закрыт.

It means a code lock, combination lock, or keypad lock, depending on context.

• кодовый = related to a code
• замок = lock

So кодовый замок is a lock that is opened by entering a code, not by using a regular key.

Because Russian замок has two meanings:

• за́мок = castle
• замо́к = lock

The spelling is the same, but the stress is different. In normal Russian writing, stress marks are usually not written, so you have to understand the meaning from context.

Here, because of кодовый, it clearly means lock: замо́к.

In Russian, the verb to be is usually omitted in the present tense.

So:

• Кодовый замок закрыт. literally looks like
• Code lock closed.

But in natural English, that means:

• The combination lock is closed.

This is completely normal in Russian.

Because закрыт is the short form, and short forms are often used after an implied is/are.

So:

• замок закрыт = the lock is closed

But:

• закрытый замок = a closed lock

That is the basic difference:

• short form (закрыт) = usually used as the predicate: is closed
• full form (закрытый) = usually used before a noun: closed lock

In this sentence, Russian needs the short form, because the sentence is describing the state of the lock.

закрыт is the short-form masculine singular of закрытый.

It agrees with замок, which is:

• masculine
• singular
• nominative

Other forms would be:

• закрыта — feminine
• закрыто — neuter
• закрыты — plural

For example:

• Дверь закрыта. = The door is closed.
• Окно закрыто. = The window is closed.
• Двери закрыты. = The doors are closed.

It is in the nominative case.

That is because кодовый замок is the subject of the sentence — it is the thing being described.

You can see the agreement:

• кодовый — masculine singular nominative
• замок — masculine singular nominative
• закрыт — masculine singular short form, agreeing with замок

Because it is an adjective agreeing with замок.

Since замок is:

• masculine
• singular
• nominative

the adjective also has to be:

• masculine
• singular
• nominative

So you get:

• кодовый замок

If the noun changed, the adjective would change too. For example:

• кодовая дверь — if the noun were feminine
• кодовое устройство — if the noun were neuter

Literally, закрыт means closed/shut.

In some contexts, English may translate it more naturally as locked, but the more specific Russian word for locked is often заперт.

Compare:

• Дверь закрыта. = The door is closed.
• Дверь заперта. = The door is locked.

So закрыт does not always mean the same thing as locked. It usually focuses on being closed, not necessarily locked.

Yes, Russian word order is more flexible than English word order.

The neutral, standard version is:

• Кодовый замок закрыт.

That is the most natural order if you are just stating the fact.

A different order is possible for emphasis, but the sentence given is the normal one for a learner to use first.

It is pronounced:

• ко́довый замо́к закры́т

The stress is on:

• ко́ in ко́довый
• мо́ in замо́к
• ты́т in закры́т

A rough English-style approximation would be:

• KO-duh-viy za-MOK za-kryt

But it is best to learn it with the Russian stress pattern.

Russian has no articles.

So Кодовый замок закрыт can mean:

• The combination lock is closed
• A combination lock is closed

Which one is meant depends on the context.

English requires an article, but Russian does not.

Yes. It is short, complete, and natural.

Russian often uses very compact sentences like this:

• noun phrase + short-form adjective

So Кодовый замок закрыт. is a normal way to say that the lock is in a closed state.