2004 4Runner Head Unit Upgrade

I'm planning on upgrading my 2004 4runner Limited head unit from stock to a newer Toyota head unit. I bought the T10015 head unit with NAV module (comes out of a 2013 Scion i think) to provide OEM looks but with added Bluetooth capabilities. I have the JBL Synthesis system in the 4runner.

Has anyone done this mod before? I am using "The Ultimate Scion Head Unit" upgrade provided by TheTrackAhead but he doesn't have the JBL Synthesis system in his 4runner. Here's what I've purchased so far:

- T10015 Scion HU
- Metra TYTO-01 harness (for JBL Synthesis signal processing - although P/N on box says AXTO-TY1)
-

$12 Metra Toyota 20-pin Steering Wheel Control Add-on Harness with RCA

Metra 70-8114 harness (for steering wheel controls)
- Metra 40-UV43 harness (the antenna adapter) + 1988-05 Antenna Adapter Tip
- Toyota

Genuine Scion Accessories PT546-74120-MC Microphone

PT546-74120-MC (Microphone kit)
-

Base Audio Wire Harness Kit

Toyota PT546-00142 Base Wiring Harness Kit which includes:
~ USB conversion cable (PT546-00120-US)
~ Antenna conversion cable (PT546-00120-AD)
~ 20 to 28 Pin conversion cable (PT546-00120-CH)

I think that's it. Here's some photos of the HU:





Just looking for some tips/tricks or things to look out for when installing all this. I'm hoping the NAV stuff just plugs directly into the back of this new HU as I haven't purchased any adapters for that portion. If NAV doesn't work, its not the end of the world as I 100% of the time use my phone GPS anyways... but it would be nice to have all the OEM functionality just because.

 

Did you end up installing the T10015?

 

Not yet… I’ve bought all the parts but the car isn’t actually mine yet (buying from my parents). Should take delivery this weekend but honestly don’t know when I’ll have the time to dig into this install. Was hoping to have all the wiring like pre done on the bench so the actual install goes smoothly.

 

Alright so I have all my wiring harnesses and am starting to get them all together. I’m trying to splice into the JBL adapter harness (TYTO-01) from the power/front speakers connector and there are two different harnesses that I would expect to be the same that I’m trying to splice into. The first is the one attached to the TYTO-01 that looks like this:



Or there is a separate pigtail I purchased that is the same plug but looks like this:



See how it has that blue wire jumper? Does anyone know which one i should splice into? Here’s just a comparison photo:



They go to the same place I’m just wondering why they are different.

 

Ok I think I got my wiring done. Ended up splicing the non jumper’d connector as that’s how it was done in the YouTube video I followed.

final outcome:

 

Well I got the Head Unit installed. Radio and bluetooth work, i can play music from my phone which is awesome. Haven't tested a call yet but i ran the mic up to the overhead console area and ::fingers crossed:: it should work.

Only issue, my backup camera doesn't work. I did not see a plug on the new head unit that was open for what i'm assuming is one of three plugs (black/blue/white) from the old head unit:



So the backup camera is important so i will need to get that figured out.

Here's it all installed:

 

Anyone have an idea if there is an adapter harness for the backup camera?

there was no female plug on the new head unit to plug the oem backup camera male plug into.

 

I think i need a female adapter from the white (top right) plug, whatever you call that one, from the 'old' head unit to a 16 pin male plug for the 'new' head unit but am stumped. I've googled my heart out but cant find one. Does anyone know what kind of plug that white one is called? If i knew that may help in my search.

 

For those of you wondering I googled and called around (even crutchfield) and they don’t make an adapter from oem JBL syntheses to scion t10015 for the backup camera. So I’m having a custom one made from autoharnesshouse.com

crutchfield kinda made it sound like they don’t make an adapter from oem JBL synthesis to any head unit. When I was on the phone with him he was like ya I don’t show any aftermarket head unit being able to retain existing backup camera. Would have to run a new camera.

 

Got the new custom harness installed. Still no backup camera. So I’m waiting for the company to write back their thoughts good news is while I was in there I adjusted the TYTO-01 harness potentiometer and damn it totally changed the quality of the sound. So the sound of the new head unit is dialed in, just got to figure out this damn backup camera!

here’s the back of the head unit with the new harness, anyone notice anything blatantly wrong with the installation?



The new backup camera harness is the bottom right of the pic then the black and brown wires trailing off that (for the reverse signal)

 

Autoharnesshouse replied to my email and asked if i can verify through the Head Unit settings that its registering when i put the vehicle in reverse. However, i cannot seem to find the head unit setting that shows me this. I googled it for other head units and know what he's looking for... like a system setting screen that shows "reverse - Off" when not in reverse or "reverse - on" when in reverse. Unfortunately, can't find that setting.

So basically there's no way for him to be sure his wiring is working correctly, or if the head unit for some reason just isn't registering that i've put the car in reverse.

Any ideas?

 

I'm thinking the signal voltages are not matching and may need a 'step down converter' (just a guess). Anyone know the OEM backup camera voltage? i'll try to find out what voltage the T10015 needs.

 

Maybe go back and look to see where the backup camera is and make sure it’s ok?



pictures if you don’t mind.

 

I'm going to take the head unit back out and check i have the right pin connecting into the 28pin connector. Like not the pin 2 slot, but the actual physical pin is correct and also make sure i seated it properly. From here and other forums i should at least be getting a black screen when shifting to reverse if its just that the voltages are different between camera and head unit. Because nothing happens when shifting into reverse that tells me something isn't picking up the reverse signal.

 

Well, I'm the idiot. I took it all apart and reexamined the connection on Pin 2 in the 28 pin connector and low and behold i did not seat the reverse signal pin correctly inside the connector. Fiddled with the pin (can't remember if i just didn't push it in far enough or if i flipped it 180 degrees to get it right) then tested it and wham bam got a backup camera now! Apparently i don't need a step down converter which is a breath of fresh air after all this.

Shout out to Brian at Autoharnesshouse.com, dude stuck with me through 15 emails back and forth throughout this whole process. His harness worked flawlessly once i got it installed right. I gave him his due credit/props.

So for anyone whos curious, you CAN do the T10015 Scion head unit upgrade in a 4th gen 4runner with the JBL synthesis system and retain steering wheel controls, gain bluetooth for phone music, add mic for phone calls through the car stereo, keep OEM backup camera, and keep the great JBL sound (once you adjust the TYTO-01 potentiometer screw). Incase it was lost in the threads, the only thing i upgraded for sound was the 8" sub... went with a Rockford Fosgate drop in replacement. The only thing i lost was navigation through the head unit (even though my T10015 came with the nav module... did not even attempt to figure out how to hook it up) but that's no biggie as i 100% always use my phone for navigation anyways.

 

gkomo this is awesome! I'm curious about the TYTO-1 potentiometer screw. My '04 SR5 came with a Sony XAV head unit and the sound is awful. If I adjust the balance and fader I can get every speaker to work and seem to have quality sound including the sub (in fact, especially the sub). However the center dash speaker dominates and there is almost nothing coming out of the rest of the door speakers (again, unless I mess with balance). I've seen on other strings, pulling every speaker and bench testing and even somebody disabling the center speaker to force power to the others. I'm going to assume (dangerous) that your Scion unit and my Sony XAV are similar. I should also take this moment to say I know NOTHING about what I'm doing though I did successfully install a different head unit in an old 94 corolla back in the day. Executive summary, new Sony XAV with horrible sound in JBL synthesis system despite what appear to be perfectly healthy speakers. Thoughts?

 

Hmm, well the TYTO-1 adapters function (from my understanding) is not only to physically be able to connect the new head unit to the existing JBL wiring, but also to moderate the signal output from the new Scion Head unit to the JBL Synthesis amp. The reason my sound was terrible at first is because I was moderating TOO much voltage down from the head unit to the JBL amp, so i 'turned it up' so to say, to allow more voltage from the head unit to reach the JBL amp.

Your issue sounds a little different as different speakers are outputting different sound levels than others. Did your system sound fine before the new Sony head unit? If so, I would think there is some issue with how the Sony head unit is dispersing sound signals to each speaker. I'm totally speaking out of my ass as i'm not an audio expert, but just based on what i know from my own experience, your issue sounds different than mine. ALL my speakers sounded like crap before adjusting the potentiometer screw... not one or others. This makes sense though as the head unit signal voltage in its entirety wasn't enough for the JBL amp to amplify back to the speakers.

 

My speakers all sound like crap too, unless I "force" the system to route power to the rear. If I don't, pretty much only the center dash speaker is audible. But I have the fader set halfway between center and rear. At this setting, the sub lights up and (poorly) balances with center dash; but still nothing much coming out of the doors. In fact, sometimes the power will fluctuate - loud in dash, then loud in sub - when I do this fader trick - it's as if the unit can't decide between the front and back when it's right at that fader threshold. So I wonder if there IS a modulation issue as you suggest. Or, maybe the JBL factory amp isn't enough? If it's even still in there!
I actually bought the truck with this system "installed" and I've yet to open things up. It would be nice to have an idea of what procedure I'm going to perform before cutting the patient! But this is helpful, I think we're on to something as clearly your JBL amp is plenty, right?

 

I should also note that I've not done a software update on the system which is likely a good idea!

 

Since you have an aftermarket head unit and it was installed by the previous owner it will be hard to troubleshoot over the internet. The factory JBL amp, although inferior to probably most aftermarket amps, should be plenty powerful enough to power all the factory speakers. It’s gotta be something going on with the way your Sony head unit is sending out the signal voltages. I would set your balance/fader settings all to like default settings then troubleshoot from there.

 

I have the same issue..Way more sound coming from the front center than from rear or doors.. I also move the sound more towards the rear to get better sound overall.. You found out the reason for this by any chance?

 

Mine has these pink and brown wires on the harness, I also see a brown wire on the TYTO harness but no pink.. Any clue if these two wires should be connected? I see you don't have them at all in your photo. Bought this harness off Amazon..

 

I don’t remember exactly, but I do remember a couple wires that are intentionally not being used. I think the directions I had said to just loop them and tie them off. I should have pictures somewhere of my final wiring product in this thread somewhere.

 

I also am having the same problems with the speakers not sounding right I took the head unit back out and spliced that brown wire back together but it didn’t do anything if anybody has figured it out lmk

 

So i looked back at my photo and your photo for that connector. That connector i believe is 'sound out' for left and right channels. I'd have to look back at what the middle pins of that connector are for, but i'm fairly certain you don't need the pink and brown wires. I would just cap them and tie them off unused, or remove them from the connector completely.

What do you mean 'not sounding right'. I still get some volume fluctuations with my set up. Adjusting the potentiometer helped a lot but there is still sometimes my sound goes from loud to quieter and back to loud, or vice versa. Its annoying, and i haven't had the time to mess with the system.

 

Ahh, I finally figured out my sound level varying from louder to quieter, randomly. I was stuck in traffic and getting annoyed about this issue that has been persistent from day one of this install. So I started messing with the sound settings looking for anything I could find that may help. There is a Audio settings screen that lets you pick which vehicle the T10015 goes in (i'm assuming) as there were options for tC, xB, iQ, FR-S and xA. I previously had it set to tC because the entire sound system sounded the best at that setting, and that's how it came. BUT, i went through each vehicle, all sounded like crap except for xB, which didn't sound great... but not terrible. WAY too much front speakers... even with the forward/rear bias set at the middle. The important thing though, I did notice the sound volume wasn't fluctuating at all. I adjusted the sound bias a couple clicks to the rear, and walah! It actually sounds great and the sound, even set at a rear bias, sounds "centered" if that makes sense.

Finally figured it out after all this time! No idea why it works going to the xB setting, but it does.