Do you know, how to connect power antenna to make the original amplifier work?
When I connect the new unit it works only with front speakers, but rear ones won't play. I found somwhere that it has something to do with the antenna power.
Any ideas?

(hope you're still checking this post, it's been a while)

on factory radios, there is an amp relay that turns the amp on when the radio turns on, and on new radios, there are sometimes multiple relays for the amp and the antenna (mine had 2). these wires are blue, blue w red stripe blue w/white stripe. on the wire harness to the truck, the two blues are to be connected, then connected to the antenna relay from the new unit. i have another amplifier that i put in, and i put the 2 relays from the new unit to the 2 blues from the wire harness (one of these blues at the harness is usually already looped to the other when you buy them, so there is only one wire to connect). my antenna comes up all the time now too, not just when fm/am is on, which is good, because most of the breaking of antennas is when they are moving up or down while driving fast. are all your other wires accounted for? i found this pdf to be of GREAT help:


http://installdr.com/InstallDocs/Toyota/PDF/869017.pdf

Thanks. That's a lot of help.