While reading the novel, the lights suddenly went out.

The sentence, in its current form, implies that the lights went out while they were reading the novel i.e, that the lights were reading the novel. We need to keep the form and tense intact and write the correct event description. Since the speaker should be the subject reading the novel, the main clause would be: "While I was reading the novel". The supporting modifier is correct. The sentence would be: "While I was reading the novel, the lights suddenly went out."