Ok If anyone else wishes to do the same as I have, here is how it works.
You need an interface between the new headunit and the factory amp. This unit is called a METRA TYTO-01 2003-08 TOYOTA JBL INTERFACE WIRE HARNESS. It plugs directly into your original plug, and sends the correct data down the TX+ and TX- wires, and also has a gain adjustment for varying your rca signal up or down to get the right level for your amp.
If you are going to connect other functions to the head unit, such as a dimmer for lights on, reverse camera etc, you will still need to splice wires into the harness.
If you use this interface you have no need to bypass the factory amp, or replace the rear speakers in order to install your aftermarket head unit. (you can have your cake and eat it).
The installation I have done gives just as superb sound quality from my aftermarket head unit as the original head unit, with all the extra functions you want these days in a Lexus.
Hi Gasso,
I have an IS200 year 2002 and want to achieve the same result and hoping you could confirm a couple of things before I order the harness:
1/ Do you have factory sat nav? - if so does it function as normal (screen activation and voice interception of front speakers) with the harness?
2/ There seem's to be different looking harnesses available:
a/ As shown on Metra's website (link below) - IS300 is listed but not IS200 but I figure this is because it is a US website and I suspect IS200s were not sold in US. Anyhow, I'm assuming the head unit / amp is common between IS200 and IS300.
As you can see the modules are different in appearance. Do either of these modules match yours? Any thoughts on if there might be any difference in function between the two? - perhaps it's just an updated housing design.
Is200 Stereo Wiring Diagram
in Lexus IS200 / Lexus IS300 / Toyota Altezza Club
Posted
Hi Gasso,
I have an IS200 year 2002 and want to achieve the same result and hoping you could confirm a couple of things before I order the harness:
1/ Do you have factory sat nav? - if so does it function as normal (screen activation and voice interception of front speakers) with the harness?
2/ There seem's to be different looking harnesses available:
a/ As shown on Metra's website (link below) - IS300 is listed but not IS200 but I figure this is because it is a US website and I suspect IS200s were not sold in US. Anyhow, I'm assuming the head unit / amp is common between IS200 and IS300.
http://www.metraonline.com/part/TYTO-01
b/ One I found on e-bay (link below) - doesn't actually list Lexus vehicles.
http://www.ebay.com/itm/Metra-TYTO-01-2003-2008-Toyota-JBL-Interface-Wire-Harness-Integration-Axxess/301184066092?_trksid=p2047675.c100011.m1850&_trkparms=aid%3D222006%26algo%3DSIC.FITP%26ao%3D1%26asc%3D22426%26meid%3D7275462331005596849%26pid%3D100011%26prg%3D9723%26rk%3D1%26rkt%3D10%26sd%3D300351534683
As you can see the modules are different in appearance. Do either of these modules match yours? Any thoughts on if there might be any difference in function between the two? - perhaps it's just an updated housing design.
Thanks for your help mate!