Sceanzo

I am picking a 97 up this weekend. It has a blown factory amp so no sound from speakers. I am wondering if I can just install a new head unit (aftermarket) to address the issue. I listen to music mainly off my phone anyway so I would get one with an AUX port. Or will I need to replace the factory amp before I install a new head unit ?

sha4000

iTrader: (1)

Pioneer or Nak? It's always better to have an amp but you can most likely run the wire from the head unit to the speaker but you will lose the woofer in the back window.. How do you know the amp is dead?

PureDrifter

iTrader: (10)

You would either need to replace the OEM amp or run new speaker wires to all the doors.

You would not be able to easily retain the factory sub without a beatsonic harness or engineering your won solution.

Sceanzo

I believe its Pioneer. You turn the audio unit on, you'll hear a small "pop" from the speakers. The speakers produce no sound. I haven't personally seen it yet, this is what the seller has told me. I have an IS350 as well and when the factory amp blew it did the exact same thing.

dicer

I have a 90 that had an aftermarket head unit install, it had a special wire harness adapter and used all the existing speakers in the car. It is a simple install or remove, I removed it.

Kansas

Are you certain that the amp is defective? Lack of sound is more often caused by a head unit issue or a problem with a phone system wire in the trunk grounding and putting the audio system into permanent mute mode.

Sceanzo

I'm not certain. I am just assuming going off my own experiences. Does the factory amp power the sub only or the speakers as well?

McPierson

iTrader: (3)

It powers everything. I'm pretty sure, you'll want to check, that all the speakers are 2ohm. Be sure the headunit you get will run 2ohm speakers.

Shun

How can u check this or unmute I have tried everything else

Kansas

Does you LS400 have a Lexus brand phone system? I don't see the model year in your profile or in this thread but the phone ECU for the 95-00 LS400 is under the false floor on the right side of the trunk. If the phone ECU is there, then unplug all the connectors from it and plug the two large connectors together. Secure all the connectors so that they don't contact the floor and possibly get wet. On the 95-00, the two large connectors can be plugged through a plastic bracket attached to the bottom of the tool kit receptacle to keep them up and out of the way.

If the audio system still is muted, check for corrosion in the phone ECU connectors in the trunk. I remember one case on this forum where the wires in the connectors were so corroded that they were falling apart.

A shorted out phone ECU is just one of the issues that can cause the audio system to be muted. The Nakamichi in my 2000 LS400 lost it's right channel due to a problem in the head unit.