The only flaw in his character seems to be a short temper.

他性格中唯一的缺点似乎就是脾气急躁。

《柯林斯英汉双解大词典》

He has a short temper.

他脾气很暴躁。

youdao

He has a quick temper. He has a short temper.

他是急脾气。

youdao

And Mr Rudd's short temper had won him few friends to call on when the final crisis loomed.

ECONOMIST: Australia changes prime minister

Whether the result is a persistent bad mood, negativity or short temper, the people around you will have to bear the brunt of it.

FORBES: Who Comes First In A Partnership?

And he has a short temper.

ECONOMIST: John McCain