new deck, speaker problems? also code 12

[toyota83]

thanks for the quick reply and info. i checked all fuses and they are all good...??

there is another wire like an RCA cable running near the antenna wire. whats that for?

i looked in the trunk by the antenna access panel and there is a white-ish 4-terminal plug not connected to anything. ideas?

again i am using temporary power from the cigarette lighter with alligator clips.

dome light does not work, but other courtesy lights do. often in other vehicles i have worked on, the radio and dome light are in the same circuit.

is there any place to get a wiring diagram for the radio and everything connected? (aside from getting a manual which i will do very soon)

thanks again