I currently have a 2011 is250 which I believe has 13 speakers, non nav non ML
sound system is ok, but I'd like it better, searched the forum and on another forum I'm on (uk based, about as much use as a chololate watch)
basically id like to upgrade to nav, head units can be bought for a few hundred pounds on eBay but don't come with wiring my question is, what wiring do I need( do they have part numbers) and with the correct wires is it an easy job? I'd be paying an audio specialist to do it but they mightn't like the idea of installing factory stuff bought 2nd hand due to warranty issues etc..

failing that id still like to upgrade the sound system, I've seen audioson do all the correct speaker sizes to suit the lexus, inc front and rear woofers - would installing a front speaker in the dash be an issue since there isn't one there currently?

does the standard head unit have a preout to fit an after market amplifier? If not how are people getting around this issue?

 

Replacing the wiring harness and associated hardware would be prohibitively expensive. Use your iphone for Nav and get a good subwoofer - it'll make all the difference!

 

Ok so nav is out the window... now for a sound system.
Seen some pretty decent audison 3 ways that should fit the doors. Having 3 ways does that mean I need a 6 channel amp just to power the front speakers? And then a 2 chan for the front and rear woofers