Use OEM Mic with Aftermarket Headunit

We are different people.

 

I performed this upgrade today and it worked great. The male-to-female cable was pricy from Amazon. I sourced the rest of the parts from adafruit.com. I tapped the 12v positive and negative on the iDatalink harness using positaps, and used five positaps to connect the microphone and power connections (with a wire jumping the two negative connections) to the extension harness using the pins shown in the first post.

Parts:
Amazon:
1 x 28-pin male-to-female wiring harness

$30 28-pin Head Unit Wiring Harness Adapter Fits Subaru and Toyota

https://www.amazon.com/gp/aw/d/B01BSE5X9Y
Adafruit:
1 x UBEC DC/DC Step-Down (Buck) Converter - 5V @ 3A output[ID:1385] = $9.95
1 x Through-Hole Resistors - 100K ohm 5% 1/4W - Pack of 25[ID:2787] = $0.95
1 x 3.5mm Mono Audio Plug to Alligator Clips[ID:4181] = $1.95

I didn’t use the 100k resistor but bought them just in case. Might try wiring one in on a rainy day.

 

So I just wrapped up this mod on my 2019 Sr5 SX. I installed a pioneer HU and really hated the idea of the after market mic and gps antenna. I found this thread worked for me, the resister does need to go on the + mic wire, but everything else is spot on.

Anyone interested there is a set of adapters sold on Amazon for like 12$ US that allows use of the oem gps attena. This model has 2 connectors a white and a black one (truck side) the black one sets my clock and works the navigation. I think the white one might be the XM radio antenna, but either way it wouldn't update my clock.

Anyway I am happy this worked for me... I hate extra wires and stuff stuck around my truck when it has the equipment from the factory. Lol I just wanted a better bigger screen with better navigation lol. Android auto is also way better than whatever my non entune radio offered.

 

Having major quality issues with the built in Dasaita mic, so I'm switching to a Pioneer and ordered the stuff to build out this harness. Any recommendations to tap 12v for the step-down? I'm thinking lighter socket but if someone knows better I'm open to suggestions.

 

Got the harness built today. Thanks to all who posted their updates.

 

Q: Are we sure 1k ohm resistor is correct vs. 100k ohm, as posted by the OP?

Personal experience:
2008 Tundra (JBL system);
Head replaced with Kenwood DNX697S using PAC RadioPro4 harness;
This harness does not use the K9 factory plug at all - which is where all the MIC wires are - tapped from behind for this;
{{{{{62k ohm}}}}} resistor placed in-line on MIC+; (Intricate solder surgery - these wires are tiny!); {EDITED: 01/08/2025}
Presuming that's the center conductor of the Kenwood MIC cable - white wire; outer wire to MIC-;
12V step-down to 5V (MIC amp power) from the ACC+ cig lighter circuit - also used for ground of the step-down;
It WORKS!
Multiple call recipients on the other end indicate my voice is loud/clear;
But they also have feedback of their own voice on a 1 second delay, though faint when I turn them down to 12-15 volume, so I can still hear them when stopped with engine running.
I hear no feedback -- they are clear.
Switch to the speaker on my cell phone and the behavior disappears so we know it's not the call
Although that took a bit of tinkering because the head-deck drops the call to the phone and returns to it's last function:
AC/DC - Hells Bells; Nazareth - Hair of the Dog; forget which - blasting at 25+ volume - the factory JBL system rocks!
It occurs to me the PAC RadioPro4 has three 'gain' DIP switches and I don't recall where they are set -- which could be the problem (might be at +7 gain).

Everything may change when I swap the harness for iDataLink Maestro RR2, although I suspect the MIC problem will not change.
Maestro uses 'line-level' outputs for R/L signal from the head-deck: always better than 'speaker-level' outputs that add distortion when being amplified, only to be stepped down again.
Then again, the factory head may not amplify much prior to the AMP under the seat.

 

Unfortunately I think the echo is going to remain for the talker on the other end of your call. I just installed a Pioneer (see my other posts from yesterday) using this mic harness and I didn’t ask about quality so it could be a blind test, and all 3 test calls the user on the other end of the line complained about their own voice echoing back to them. I do want to say that I don’t think this is specific to this harness, but to CarPlay in general. A quick search for whatever head unit you can think of plus “echo” will return results on this. Even Grom. I have no idea. Now, on my 2nd Gen Raptor no one complained about echo but it did not have wireless CarPlay, it was only wired, and calls were clear with no echo so that might have something to do with it as I don’t have a USB split, unless the Maestro I have keeps the factory USB and allows me to power the mic off the Pioneer USB.

 

It must be the hardware!
The RadioPro4 harness is uninvolved because the MIC+/- wires are directly from Toyota HU (2008 - K9 plug) to the Kenwood deck MIC input (plug-in).

The math is a bit over my head and I googled-up a blog which aids understanding of theory: https://intshop.jzmic.com/blogs/blog/microphone-impedance-how-does-it-matter

Although they're discussing guitar / amp / sound equipment tech, this stands out:
((redacted))

 

Good luck to you, I hope it works out and keep us posted.

 

You could also put this mic in the same location as the original factory one
https://shop.enfigcarstereo.com/product/enfig-mic-toy1/

 

Doesn't show compatibility with Tundras. I looked in the reviews as well without any feedback from Tundra guys. Any confirmation it'll do for us? The Pioneer mic ain't cuttin it for me.

 

https://www.tundras.com/threads/rainmans-2021-lunar-rock-trd-pro-build.77317/page-29#post-3332914

It fits in my 2021 overhead console, and the mic spot (no longer used in the 18+ trucks when they moved the mic over the driver’s head) in it is the exact same as the one I had in my 2008 truck overhead console.

it’s working fine for me.

 

Good nuff for me. Thanks Casey

 

I’m not uninstalling this damn radio again.

I’ll probably be uninstalling the radio again


FML

 

Once someone confirms whether or not this (or some variation) will work I will immediately do it. The feedback on this is maddening. Doing a quick search shows that it is a CarPlay issue and not specific to vehicle brand

 

I threw in the towel after a few modification rounds of trying to get it to work. Frankly it's just not worth the effort, the sound quality's better with any decent aftermarket headunit included mic and routing the cabling is much faster than this harness workaround attempt that never actually worked out for me. It's a neat theory but execution just didn't work out for my 2016 non-JBL headunit's wiring. The

$875 Kenwood DMX1037S 10.1" High Definition Car Stereo Receiver with Capacitive Touch Panel

Kenwood DMX1037S I installed just sounds worlds better to phone callers and quality than the OEM ever did.

 

That's very tempting versus this over saving the factory mic

"I don't wanna work. I just wanna all day." But the joy is in the journey and if I do figure it out ...

FYI for 2nd Gen Tundra...
PAC RadioPro4 and iDataLink Maestro RR2 have similar problems in the harness:
1) AVC-LAN (CAN H/L) system originates from multiple locations (they both misdirect concerning DLC3: 6 and 14), and
2) There's no provision for the K9 plug (wires are MIC+/-, MIC 5V/shield, SPD), and
3) 2nd Gen Tundra has the issue of no PKB / REV in the radio harness.

I attached a Whiteboard in progress for those who think

Note:
I hacked the PAC harness down to only what's needed for 2nd Gen and I have NO INTENTION of installing both at the same time!
Where it says ?Audio Cable? I believe that's the AUX-IN lead (R/L). Problem is that I want Video-In with it, although the Kenwood manual says you're limited to (AUX-IN) or (CAM4).

 

Holy Sheeeiiiitttt……on second thought I will just deal with the echo!!!!! That is way above my paygrade

 

Long story... short:

I figured it out ?? ohm in the MIC+ line is perfect!

If you have a 2.5 Gen (+) Tundra, there is no K9 Plug ... your pins will be as pictured near the beginning of this thread. [Ed.Note: at the 28-PIN Plug]

This is for Kenwood DNX697S in a 2008 Tundra (with JBL and with or without Navigation):

K9 Plug (16-PIN: You must cut or strip, and solder to back of the plug):

1) Plug K9, Pin 2 (BR) = MIC+ w/ 75k resistor in-line [Ed.Note: 11/19/2024 after discussions w/ Mr. Keith -- 75k is a very 'safe' high number. Up here, sensitivity / dynamics will be reduced. If you get below about 40k, you will have feedback -- which is the 'echo' everyone complains about. ie: It is NOT CarPlay!]

2) Plug K9, Pin 1 (Y) = MIC-

3) Plug K9, Pin 7 (LG) = MIC Amp Power... 5V

3)a) You can use Plug K9, Pin 16 (GR) for this:

3)b) Pin 16 is 12V (ACC)! This must be stepped-down to 5V, which goes to Pin 7 [Ed.Note: PIN-5 is Batt 12V+ and it's on Radio Fuse #1. But the MIC would be powered-on 24/7]

3)c) For GND, Do NOT use Pins 3 or 6! Use Pin 14 (W-B). 3 and 6 say GND in the schema but loop back on each other in the harness (through the TOYOTA radio you've removed). 14 is truly to GND.


Short story... long:

Jim at Norvac Electronics said, 'You might try a ??? ohm potentiometer and pin it down exactly,' which I did (PIC attached) and then tested/verified by calling two friends, in California (trucking) and Nevada (at home).
(Long story even longer: I consider both 'good' friends, having met both at different roller skating rinks 30+ years ago. So, we're fellow Rink Rats, and proud of it!)

With Volume cranked to 30 and... "Can you hear me now?..." repeating from my speakers...
Resistance at ??? ohm: my voice is muddled to them and echo/feedback (w/ 1/2 sec delay) is through the roof.
Resistance at ??? ohm: my voice is good/strong and the echo/feedback is faint though present.
Resistance at ??? ohm: we were having a clear conversation; they may have noted a hint of echo on occasion.
Turn the Volume down to 25 -- PERFECT -- with no echo! Yet, loud enough to hear them w/ the windows down going 60 MPH.

Of course, I still need to install the ??? resistor and wrap the factory harness again.

Then onto the rest of the harness after an apropos midnight supper: spaghetti with meatballs and wild foraged hedgehog mushrooms.

 

One more PIC:
12V (ACC) step-down to 5V for K9 Pin 7 (LG), using 20ga wire.
MIC+/- (Pins 1 & 2) are also in the background.
Really struggled with soldering the resistor in MIC+ (flux paste helped) ... It's also double heat-shrink wrapped so jarring or pulling will not break the strands.
All wraps nicely w/ a bit of harness E-Tape: Step-down exposed for cooling air.

 

Great job man. You're a tenacious one and if I wasn't going the enfig route, I'd end up going this route.

 

This mod cost less than $5.00
(Ignores time, $4.50 pot, 2 - 100 ft rolls of 20ga wire @ $25ea, solder/paste, heat-shrink tubing and $30 Kenwood mic [I paid $10]. There's a comparable MIC at the rainforest which includes a wind-guard for $6.99)
GTT is then less than: $11.99

 

Bought a 5 pack of wind screens for $5 on Amazon so hey even cheaper

 

The EM locates Junction J77 right behind the radio. And (after slicing the harness wrap) there it is!

Right in front of you, REV goes to J77 Pin 6 (V). DNX697S wants this for tailgate Cam trigger.

Uh oh! Also pictured is the MIC+ resistor I actually installed: ??? ohm. Tested this w/ my neighbor's cell phone. It's fine! (Don't go any lower though)

 

I appreciate your effort and persistence on this. I kind of wish I hadn't given up so easily but I was too busy and had to operate in an install/return window. I do hope that everyone that tries this reports back. Good stuff!

 

I can guarantee you that if you were able to produce plug and play harnesses, people (including myself) would be willing to pay a premium for your time and effort!

 

I second that.

 

I’ve been looking for something like this. I’ve got a Pioneer 7600. Call quality on the other end is pretty poor sometimes. Wife’s 4Runner also has Pioneer with the same issue. I can’t decide if it’s the mic or the location. Gonna give this a shot. Thanks for sharing!

 

... (This thread is about SAVING THE FACTORY MICROPHONE when you install an aftermarket Stereo)

I may have missed my calling -- love this techy stuff! The thought of mass production has occurred!
Fairly simple (for me) to assemble small scale, a kit needs a catchy Model number, like: CAR-MIC-SVR
Installation instructions need research. Kit could apply to many more vehicles than 2nd Gen Tundra, possibly universal.
Shoot-the-moon: 1M production and $15 price point. (Yikes!) I need to change the subject - now!

I spoke with an ADS - Maestro Tech (Chris) this morning: "Top Notch!" customer service.

1) They won't share their Maestro RR2 pin-out diagrams - obvious reasons.
2) But Chris affirmed I need to move two (or three) PINs in their TOY harness Plug-B (my K3 Plug) to get AUX-IN where it needs to go-- to the head-deck, AUX-IN plug.
2)a) They state "...retention of AUX-IN..." because technically: Maestro RR2 is bypassed.
3) The TOY1 harness is tailored to Gen 2.5 and up... anything with a 28-pin connector. (So, Gen 2 requires some manipulation)

Since I now own all the major brands, and can only install one of them:
CRUX, PAC, ADS (did I also mention Banks Power: iData?), I'm thinking what have they all missed?
How many Gen 2 Tundras are out there? What other vehicles might fall into this CAN system early-design abyss?

 

Today, Kenwood DNX697S / Maestro RR2 are installed and the factory MIC is performing flawlessly!

One more PIC (owners of 2.5 Gen+ will like this)... especially those that have installed the Maestro kit...

On my earlier whiteboard PIC, you can see the Maestro (optional HRR-HRN-TO1) harness lain out and labeled.
If you spy the area labeled 28-Pin (alt), that's the optional Maestro Plug C and ... it has a red 3-PIN plug (the male pins) sticking out of it, although Maestro is not using them for anything!
But those pins are: MIC+ / MIC- / 5V+ and other than a ground (there's one right there under the letter C -- REV/PKB/SPD pins are also there -- but Maestro is not using them either?), all my kit lacks to be plug & play is the female end of that plug.
(I'll keep looking for it as I 'tool up' -- For the other two brands, a 28-PIN Male/Female pair could plug & play in between theirs and the vehicle (2.5 Gen+).

FYI: The PIC below shows that 28-PIN plug for all three brands... Maestro is the only one that has pins tapped at the MIC locations.
For the other two (and for all 2nd Gen Tundras), some bare wire soldering will be necessary. (And PAC ... has the honor of being my primary guinea pig obviously...)