I'm screwed. I have a a Vaistech iPod adapter thing, and it never quite worked right. About once a day, sometimess more often, sometimes less, the thing would appear to power cycle itself and restart the song. I could tell this happened because it would try to press "I Agree" again, but instead ended up panning my map.

Anyway, it's gotten pretty bad lately, and was happening even when listening to the radio or cd. The resets got worse, and at night I could see that all button backlighting would briefly go out and on again. Later, it got to a point where the audio system UI would not respond. I couldn't change volume, switch tracks, switch inputs, nothing would work. I finally got tired of it and unplugged the Vaistech device. The harness cable is still plugged in.

Unfortunately, things didn't get better. At this point, when I turn on my car, about 80% of the time, the audio system is says "Audio Off" and won't turn on. The lights for buttons are also off.

It sounds like something is seriously wrong... perhaps a blown fuse...

I would take the car to Lexus, but I've also modified the cables to enable Track List information while driving and shorted the parking brake sensor to enable DVD playback while moving (Although, I have never used that feature)

Anyway, before I go back and finish removing the Vaistech harness, I was wondering if there are other things to check while back there?

I don't know where to begin in troubleshooting this. I'd obviously like to take care of this myself, as I don't know if Lexus will look too kindly at all the spliced cables back there.

If I were you, I'd order new cables that you tapped into, and if that did not solve your issue then take it to the dealer. This way your tracks are covered.

I'm not sure that will be possible. Where does one get a new wire assembly? This is the harness, wires, connectors, etc. The original poster is right though, if Lexus sees any hackery going on behind the unit they will likely deny a warranty repair. The risk of being out $4,000 on a new nav/ML unit was enough to keep me away from doing anything to it, or attaching any aftermarket accessories.

That is the inherent risk you face if you hack, and things go wrong. Is it really worth the risk?? That is a personal decision. For me, it is not worth the possible repair $$$ if something goes wrong, and Lexus denies warranty coverage.

If you ordered new cables, wouldn't Lexus have a record of that, and want to know why you ordered them, and question why you were asking for a warranty claim on the same related electronics later on?

well, look in the manual to see where is the fuse for the head unit? check that fuse. remove all the vaistech cable, turn the car back on, working? no?...reconnect all the cable that you've cut and turn the car back on see if it is on...? if it is still not working, bring it to dealer....I think that what I'm going to do, if i was you....

Well, the fix could be as simple as changing out a fuse. Does anyone know where the fuse for the audio system is?

I would agree with those steps, but if that doesn't work you're stuck.

I wouldn't bring the car in with the funny looking cable that was hacked. I have heard that if a Lexus service tech has seen something non-OEM they note it in their records and it stays in their electronic record of the vehicle FOREVER. They will try to deny all claims against anything related to or connected to the modified parts. If you bring it in for the warranty work I think you will need a new cable/wiring harness.

To defeat any possibility of them linking that purchase back to you, have a friend order them, and order them through not your normal dealer, someplace like Sewell Lexus or somebody.

True, but who's to say he [the OP] has to do the ordering. Was just a suggestion nonetheless but it sounds like you may not be able to order just the harness in question [if that is the source of the issue] - but it's worth a look into IMO.

Fuse box on the left side under the dash.

Koz

first of all, I'm not trying to say anything bad at all....(to any body)...
He chose to cut the cable...if it is not working that's his responsibility.
If he's not bring his car to the dealer, what he's going to do? let it be as that condition? (if he can live with it).
He's going ask his friend to order a cable? which cable? If I remember correctly, he has to take off some parts of the dash (or the hold dash) to replace all the cable that he cut.......

Had the same problem...

I removed all the hacks I had and brought it back to the dealership. I didn't replace the cable hardeness.. I just electrical tape it up and made it look OEM..

took it to the dealer.. turns out to be the amp in the trunk

I suggest un-doing the hack and bring it in... the dealer will let u know if it's going to be an amp or nav unit..

if they say it's the nav unit.. tell them u need the car for the weekend.. and bring it back home... at that point u will need to replace the harness....

but I doubt it's anything you did...

how long ago did you install the ipod integration? did it ever work right?

I installed the ipod integration last december. It worked fine initially, but I'd experience resets after extended duration. I eventually got Vaistech to replace the unit, but the problem didn't completely go away. It was only over last two months, that the problem started resetting the whole system.

To answer your question, no, I guess it never worked quite right. And if the amp is at fault, then I'm not surprised.

Well, I removed the Vaistech harness cables, (I had only removed the Vaistech box before), and the ML system is now working. I suspect that the Vaistech harness cable is defective (or became defective), causing my original headache. I'll leave the system as is for a week to see if things are REALLY fine.

Good to see you have solved your problem. I'm always leery of attaching any aftermarket device to the navigation or audio system. I have yet to see one work perfectly as advertised and stay working for any extended period of time. Only bad things can come of it. Now if Toyota or Lexus come out with one that they can put their stamp of approval on and guarantee it works then that's another story. At least then if something goes wrong you have somewhere to go to complain or have the work done properly.