分からんが

I don't know, but

→ 分かる

phrase Uncommon #10,117

I don't know, but 分からん is an informal form of 分からない, meaning “don't know” or “don't understand.” が means “but.”

JA: 何が起きたのか分からんが、先に確認しよう。

EN: I don't know what happened, but let's check first.

I don't know, but it's a considerable amount.

— フォーリング・ダウン (1993)

I can't do it... Why? I don't know.

— アバウト・タイム～愛おしい時間について～ (2013)

I don't know if you'll like it, but give it a try.

— タクシー運転手約束は海を越えて (2017)