Learn Hardcore Finnish: Johto katkesi, joten kahvinkeitin ei toiminut. - The cable snapped, so the coffee maker did not work.

Here johto means “(power) cord” or “cable.” Although johto can also mean “leadership” or “management” in other contexts, in everyday speech johto often refers to an electrical cord.

What is the verb behind katkesi, and what form is it?

The verb is katketa, an intransitive verb meaning “to snap,” “to break,” or “to be cut off.”

katkesi is the 3rd person singular past tense: “it broke” or “it got cut off.”

What’s the difference between katketa and katkaista?

katketa is intransitive: something breaks or snaps by itself.
Example: Johto katkesi = “The cord snapped/broke.”
katkaista is transitive: someone breaks or cuts something.
Example: Hän katkaisi johdon = “He cut the cord.”

What does joten mean, and how is it different from koska?

joten is a coordinating conjunction meaning “so” or “therefore,” introducing the result of a previous statement.
Example: Johto katkesi, joten kahvinkeitin ei toiminut.
koska means “because” and introduces the cause. It sets up the reason for something. You could rephrase the sentence with koska, but it changes the structure:
Kahvinkeitin ei toiminut, koska johto katkesi.

Why is there a comma before joten?

In Finnish, you separate two independent clauses with a comma when they’re joined by conjunctions like joten, mutta (but), siksi (therefore), etc.

What is kahvinkeitin, and why is it written as one word?

kahvinkeitin is a compound noun:

kahvi → kahvin (genitive singular of “coffee”)
keitin (“maker” or “device”)
Together they form “coffee maker.” In Finnish, such compounds are normally written as a single word without spaces or hyphens.

Why is it ei toiminut instead of ei toimi or ei toiminnut?

Finnish negation uses the negative auxiliary ei plus the connegative form of the main verb:

For present tense: ei toimi = “doesn’t work.”
For past tense: the connegative is the past participle toiminut, so ei toiminut = “didn’t work.”
There’s no double “n,” so toiminut is correct, not toiminnut.

Which case are johto and kahvinkeitin, and why?

Both are in the nominative singular, because each is the subject of its own independent clause. In Finnish, the subject stays in the nominative even in negative sentences with ei.

Is the sentence’s word order fixed? Could I say “Kahvinkeitin ei toiminut, joten johto katkesi”?

With joten you normally place the cause first, then the result. Reversing them as in “Kahvinkeitin ei toiminut, joten johto katkesi” sounds odd. If you want to start with the effect, use koska:
“Kahvinkeitin ei toiminut, koska johto katkesi.”