Another JBL amp bypass thread

Last weekend I started installing a new backup camera by drilling a hole in a new tailgate handle. I removed my headunit and installed the rear camera wiring and then routed it along with the Amp bypass harness. I removed the center console and fished the harness under the carpet to the rear driver corner of the cab. I pushed a broom handle under the carpet from the rear door to the center console and then zip tied the harness with rear camera wiring to the handle. I then pulled it all through under the carpet. I thought I might have to remove the driver seat rear bolts but there was enough room. Now I just need to route the rear camera wiring from the cab to the rear tailgate.
I've been driving around with my center console on my back seat for a week so it's good to have it mostly back together.

 

You may have already noticed but if your 05 DC is same as my 04 DC, there is a grommet hole about where red circle is. The cable that goes thru that hole goes back to LH rear lamp assembly, which I wire tied the camera cable to. For me that was perfect for the camera cable route. If you remove the LH lamp assembly, there should be about 1/2" hole at bottom of lamp assembly that the little connector with cable should be able to pass thru.

 

I didn't realize that the grommet was right there. I will use that wiring route. Thank you!

 

Hey OP or @shifty` or anyone else who's used this metra/axxess combination of items... Have you figured out a way to get the illumination/dimmer function to work?

With my current PAC audio interface behind my Pioneer, my HU dims when I turn on the headlights. So I think the wire exists somewhere... Crutchfield was not helpful... All I know is my PAC is picking it up somewhere. It would be nice to be able to pin this into the metra kit....

 

I don't want to be the first to chime in on this, but given my newly upgraded Alpine head has an illumination/dimmer wire (IIRC), I was curious too.

Granted, my truck takes 70-8121 harness, which is different from the JBL which calls for 70-8117. Both have 2 plugs, one for amp/speaker translation, the other for power/ground translation. On the 8121, you have an orange dimmer wire on the Metra's power harness. On the 8117, it doesn't show one (see below) and I don't know why. Clearly, the power layout on that one OEM plug appears to be the same 20-pin (On DC looks like R15 for 8spk/no-nav, R14 8spk/with nav?), and either pin 2 or 19 (unless I'm looking at connector backwards, then it's 12 or 9) is the illumination lead. Illumination appears to use a white w/green stripe wire on the (-) side in some places, green for (+)? Maybe @BubbaW can solve that mystery. Man I suck wit hthese diagrams!

The OEM radio has to get dimmer info from somewhere, where would it grab it from? So I went to the definitive source: the EWD. I dug through every EWD for all the stereo variations I could find in 2006 and

I did order a harness/adapter to utilize the speed sensor and reverse signal wires found on the 05-06 trucks. Don't want to link it until I see the quality. My new radio model has a speed input wire, so ... may as well use it, right?

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Hey Shifty!

I also saw that the 70-8121 harness has illumination on the main power harness, while the JBL 8117 does not. I don't have confirmation that my truck doesn't have a wire in that PIN, but the rest of the pins are the same. for the remaining 4 wires.

Ok, so I've done a little bit more digging on my PAC RP4.2-TY11, I don't have an exact diagram for what is coming from the truck, but sure enough it has an orange illumination wire. This interface plugs into the truck's SWC and radio main harnesses, as noted in your picture.

I surveyed some other products, most notably the Crux CS-TJ20. In reading the installation instructions I noticed that the TYP-B connector on page 3 seems to be an SWC connector, with the diagram to the right noting an orange illumination wire. Could it be that on trucks that have the JBL amp, that the signal is picked up from a wire on the SWC harness instead of the main power/radio harness?

I may pull my radio to confirm with a test light and check both the main harness as shown on the 8121, and the swc harness as well?

Lastly... I am wondering if I can just skip the metra SWC stuff, keep my PAC as hooked up, and just divert to the 8117 at the radio harness such that the PAC gets no audio signals... Wonder if it would still work... That or just PIN an extra wire into an adapter harness when I find the source... If I can find the correct pins... I never know how to do that stuff...

 

Is this regarding your Pioneer MVH-1400NEX ?
If so, that radio should have an orange/white wire that if hooked to what the instructions say.... "To lighting switch terminal", whatever that is, it dims with headlights.
What wire did you hook that feature to in your 06 ?

 

The orange wire in my HU goes to an orange wiring harness that goes into a PAC audio interface. That interface then has another harness that connects to the trucks factory connectors, the main/radio and the SWC. I am simply saying that it is proof of concept that this function works. But the amp bypass + metra SWC that a lot of members use does not seem to maintain that function.

 

Proof of concept ?
Illumination function which others are talking about is different than a radio dimming when head lights are turned on, so undoubtedly you don't have an issue ?
Back I go

 

I am trying to make head or tails of the EWD but I am garbage at this. Guess I'll try and match this R connectors... The SWC one which may have illum is 10 across and 2 tall...

 

You won't find it in the factory radio connectors given they don't have illumination.
See further for truth.

 

Are you saying that factory radios don't have backlights? That doesn't seem likely.

Something is telling my radio that "headlights are on", and I imagine that some signal was telling the original radio the same thing. I am not looking for a "dimming" function, it's just what my radio happens to do with the signal it is receiving that is going through the "orange" illumination wire on the radio harness.

 

I'm not saying that at all. Our radios do have backlight but they're not designed to adjust the illumination nor are they designed to dim with headlights.

You imagine incorrectlyTruth....you imagined correctly

Totally agree, which I commented on in my first post to ya....follow the orange wire !

 

I think we are saying the same thing, differently.

Find where the orange wire is getting the signal.

 

Works for me

BTW....which factory radio did your DC have ?

• Audio System with RSES (DC)
  
• Navigation and Audio System with 8 Speaker (DC)
• Audio System 8 Speaker (DC)
  
• Audio System with 6 Speaker (DC)

 

I have no idea. PO removed it. All I know is it's JBL with factory amp. So it's 8 speaker, no rear controls, no rear screen. Not sure how else to tell.

 

Hey @shifty` and @BubbaW

You know what's funny? That exact PIN with the orange wire in the 8121 kit is the illumination signal on my JBL DC. I tested it from the truck all the way to the radio and it's the one.

First I had to unleash this spaghetti monster.


Here's the photo proof. Orange wire, lower right. I called crutchfield, they are no help. Called Metra and sat on hold for a long time.

 

First thing to isolate is: 8 or 6 speakers?
Second thing to isolate is: RSES (Rear Seat Entertainment System) or not? If no DVD screen (and maybe center console controls?) you don't have RSES.
Third thing to isolate is Navigation or not? Once you eliminate the middle two options in his list, you're golden. But w/o factory head unit, tough to say. I'm going to assume it didn't, but I don't know DC.

This is what I needed to see. Whether or not the OEM radio supported internal dimming. It would make sense they DO NOT, because I can't find a ILL/ILL+/ILL- wire in the radio harnesses anywhere. I see it's something that exists in other harnesses adjacent, and no doubt there's a wire you could Positap off which plugs into the back of the center dash bezel, but ... that also begs the question: Why in the hell did Metra bother putting that orange Illumination wire on the non-JBL harness if it's not something which exists in the factory harness?

(And I think the answer to that Q is: It's because the power side of that harness is used on multiple Toyota vehicles, and the cost of replacing that one wire in production for our 05-06 which don't have illumination, versus the other models that do, outweighed the cost of leaving it in there.

 

I wanna see what's in the factory side of the harness on the other side of that wire - what color wire is it? Is it that green wire that mates with the orange?

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Was just typing same and is that empty connector part of the factory hookup, meaning were there 3 connectors for the factory radio ?

 

@shifty` I think your harness is right, and my 8117 is the lame/wrong one.

It is the green white with silver markings here's two pics

Top (as oriented similar to previous photos)



And bottom, green wire is easy to see here.



Anything else before I put my dash back together?

 

The only empty connector is the gray one pictured below.



Other empty connectors are HVAC and center console stuff, and stray adapters on the PAC

As for the radio connectors, here are the faces to attempt to match to diagrams.

SWC


Main

 

You're missing what I'm asking.

What color wire is on the OEM side of the 20-pin harness. i.e. what color wire connects to the orange ILLUM wire?

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Maybe more clearly:

• Attach the adapter harness to that OEM harness.
• Flip the harness over so you can see the orange wire, and the OEM wire on the other side of it

Basically I'm looking to trace what color OEM wire would pin into the orange ILLUM wire

 

And just to prove it. All I'm doing is rotation the headlight selection on the stalk. It's on with parking/drl and full headlights. I tested with both key on and off. Same same for this circuit.

 

Scroll up! Also that's the swc plug not the main one!

 

Oh shit. DUH!

 

If I'm reading my own photos right. The location with the blue wire doesn't even go anywhere on the factory connector... I'll probably just repin that blue into the illumination spot... Despite me really wanting an orange wire and new pin...

 

The only drawing for a 2006 DC with pin 1 as blue/yellow showing above would be "Audio System<8 speaker, Double Cab>" and pin 1 is signal BU+B protected by 20A RAD NO 1 fuse, which is 12vdc straight from battery to maintain channel memory, etc. How they have altered where turning headlights on causes that I can't say but it is not factory for sure.

Attached 3 pages from EWD showing same.

 

That sounds right actually. It's pin 2 (I think) next to it with the green wire in the truck connector that is switched via the headlights. Just to clarify, when I say repin blue, I mean the blue wire on the metra comnector since there is no corresponding wire I can see in the truck connector.