I think we need a little more information to help you but I'll make a few basic suggestions to get you started. You need to isolate each piece of equipment to verify that it's all working. I'm guessing that the amp is already turning on if you are hearing white noise. Does the noise get quieter/louder if you adjust the gain on the amp? What about if you adjust the volume on the head unit?
1) Verify everything is actually turning on, there should be some type of little LED that shows that it's on. If the amp is not turning on you can temporarilly turn it on buy supplying the amp remote input with 12V (you can just use a little jumper wire from the main amp supply wire).
2) If everything is indeed on then you need to verify that the amp is getting a signal. You can test this in a variety of ways but a quick and dirty way is to get an adapter that plugs into your Ipod (or whatever) and has an female RCA on the other end . Turn the amp gain all the way down and then plug the Ipod straight into the amp with the volume on the Ipod at zero. Turn up the Ipod and amp gain slowly and if the amp has power you should hear something on the speakers. You can use anything that has an RCA output to do this, even a home DVD player. Just the amp a signal somehow.
Report back on your findings and I'm sure we'll have more suggestions to get you :beavbutt:
Exactly what does that harness do..............because there are no Line-level outputs on the AVN30D, only speaker level outputs. You may need to install an LOC to provide a signal to the stock amp.
The internal amp on the 30D is probably better than the stock Toyota amp.
I have been able to isolate the problem to the head unit. This unit does not come with RCA outputs but I was able to get the proper harness from Eclipse to fix this. When I bench test the radio with the new harness I don't get sound from the RCA outputs but I get sound from the straight line speaker wires. It is as though I need to turn on the RCA outputs on the radio.