If-person sees himself as asking-dead person about anything regarding the dead persons or anothers condition then the answer of the dead person will be true to its word- whether good or bad- for the dead person dwells in the world of truthfulness ie. Akhirah- as opposed to the world of falsehood ie dunya- . Thus, he does not speak-lie in whatever report he gives.
More related Dreams in this S For Islamic Dreams interpretation Use search box and enter phrase (translation enabled in most languages )