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Discuss Custom or Factory Audio Systems

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 #392626  by LUNAT1C
 
A lot of folks prefer to use factory audio system components in their LHs both for simplicity (plug and play) and to maintain that “factory look”.

Of course many of us, myself included, have gone the aftermarket radio route in order to get full custom audio system expansion and newer-than-early-2000s technology. One shortcoming of this is the microphone used for hands-free calling.

Chrysler’s uConnect system elegantly builds two microphones into the interior rear view mirror. Aftermarket solutions involve a small microphone having to be placed somewhere as inconspicuously as possible.

My car has had four different radios in it. First the factory installed RBB, then an RB1, then an old 2010 model Kenwood satnav unit, and now its current Kenwood DDX-9903S system that offers me front and rear camera support, and Android Auto/Apple CarPlay connectivity, giving me the Google Assistant (or Siri) plus Google Maps just a “Hey Google” away. The microphone found itself tucked up into the far upper drivers side corner of the windshield. This was fine, but once you know its there, it might bug you like it bugged me.

Fast forward to last year, I found a uConnect mirror sitting on the seat of a yard car, the first I had ever found. I grabbed it along with the couple inches worth of pigtail still attached from whoever had cut it from whatever car it came from (found it in a 2nd gen 200, I doubt it was stock there).

I did a little bit of Googling one day and found a pin out for the same system in a Dodge Caliber, only difference being additional pins and wire colors, and also located the pin out diagram of the standard 3.5mm audio jack used by stereo microphones included with aftermarket radios.

I figured it wouldn’t hurt to try. I picked up an inexpensive shielded 10+ft stereo 3.5mm cable from Microcenter and cut one end off, checked the pin out with my multimeter, and soldered the wires to the corresponding pins on the uConnect harness pigtail. I then plugged the harness into the mirror and to my Kenwood radio, called my better half, and found success! The radio was using the mirror microphones to pass my voice over to the person at the other end, and with good clarity. I don’t know if the radio uses the microphone or the phone to use the “Hey Google” voice control, but that was working as well (I did not check with the phone outside the car, like I did when testing the hands free calling).

I’m sure others may be interested in how to do this as well, so here is a how-to.

First step is collecting the hardware and needed tools and materials:

3.5mm stereo 3-pin audio cable - 10 feet or more - you know it’s a 3 pin when there are three metal cylinders on each plug instead of four. Note: not all stereo cables are made the same. The ones I have used are the QVS brand sold by Microcenter. I found a set of cables from Amazon did not have individually jacketed internal wires, rather three sets of stranded copper that likely had a very thin coating on each strand - I could not use this cable at all
Uconnect mirror itself
Uconnect mirror harness pigtail, specifically the rectangular 12-pin plug, with as much factory wire length as you can get (more than a foot if possible, but a few inches works in a pinch)
Solder
Soldering iron with fine tip
Heat shrink tubing, two sizes. 3/32” for the small gauge cable wires, and something over 1/4” - 3/8”-ish for the overall harness when wrapping in tech flex
Tech flex wire sleeping, 1/4”
Wire cutters
Wire strippers
Scissors (for the tech flex)
Electrical tape
Heat gun

Step 1:

Cut one end from the stereo cable, then strip several inches of outer jacket. Inside you’ll find three very thin gauge wires, strip them as well. Be careful, the gauge is so thin that cutting the copper is easy to do.

Then, using a multimeter set to check resistance (Ohms), check your cable’s pin out. Each internal wire corresponds with one of the metal cylinders on the 3.5mm jack. I drew a small picture of the jack and noted which portion was connected to which wire.

Slip the smaller heatstrink over each internal wire, at least an inch or two away from the exposed copper (soldering heat may travel up the wire and shrink the heatshrink, so give some space).

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Step 2:

If necessary, clean up the uConnect cable by removing any factory tech flex and removing any headliner hotmelt from the wires. You can soften the hotmelt with the heat gun on low to help remove it and get the harness clean. Then, strip the three wires corresponding to the diagram below. The harness I just worked with I believe came from a minivan, which did not have all the same pin cavities filled, but the pin out is the same regardless of what car it comes from. The Caliber pin out I worked from shows an additional pin, which I noted. The three wires in particular also happened to be twisted together. The positive leads for each microphone came from cavities 4 and 6, while the common ground came from cavity 12, which I marked on my notepad. I unraveled them a few inches to splay them out and stripped a half inch away.

The extra wires can be left still pinned into the connector, or you can depin them from it. I chose to leave them, in case I could find a use for them. One of them is a signal wire for the factory hands-free system, I assume the phone button on the mirror. The other is a sensor wire. I’m hoping to find a way of making the phone button a hard button for calling the Google Assistant, but that might require a degree in electrical and software engineering…

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Step 3:

Now we solder the wires together. My hands are extremely jittery, so I used a set of “helping hands” These are very helpful, but optional. Using the diagrams and wire colors that I noted (note that these may not be the same colors you have, so use a multimeter to figure out what each wire color corresponds to on the cable you’re using if its not a QVS cable from Microcenter).

Again the stereo cable has very thin gauge wires. Ensure the solder flows throughout the joint and securely to the small wire, making the joint strong.

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Step 4:

Slip the aforementioned heatshrink over the solder joints and shrink it, to protect them and prevent shorting. You can then fasten the wires together by a bigger heatstrink or using electrical tape to wrap it all together. I used tape since I’ve found heatstrink tends to stiffen the wire. I would also wrap the two loose unused wires if you chose to leave them in the connector. This will help make the next step easier.

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Step 5:

Now we make it pretty by wrapping it all in the tech flex. Slip the bigger heatshrink tube over the tech flex and feed it over the remaining 3.5mm connector. Once it’s over the wire a few inches you can then Chinese-finger-trap it over the entire harness. This will take time. I did a few inches at a time, then spread it along the length of the harness, until it got to a couple inches from the mirror connector. I then cut the tech flex at the 3.5mm end, slipped it the rest of the way on, slipped on the heatstrink at the 3.5mm end, and shrunk it down.

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Step 6:

At this point I would check that the harness works. Using the multimeter, confirm once more that each connector point aligns with the appropriate position on the 3.5mm jack.

If all is well, time to install on the car. If you’ve run a microphone for your aftermarket radio already, then the process is the same. Remove the A-pillar for whichever side you’re running the cable down (I did the drivers side), along with the dash end cap and knee bolster. Remove the radio bezel and the radio. Start by connecting the harness at the mirror, then tuck it into the headliner with enough slack for the mirror to move. Run it down the A-pillar, using electrical tape or factory wire runs to help hold it to the metal. Feed it into the dash, across to the radio opening such that it’s not going to be caught by the column, and keep it tucked away. Use tape or factory runs or zip ties as necessary, and pull it through the radio opening. Reinstall the knee bolster, end cap, A-pillar.

Connect to your radio’s 3.5mm microphone port, reconnect and reinstall the radio. You’ll wind up with a few feet of extra wire, so wrap it up and tuck it out of the way.

Power up the car, connect your phone by Bluetooth, and call someone. Confirm everything is sounding clear, make dinner plans if this is your spouse and they remark “this is the only time you call me!” Snap the radio bezel back in, and enjoy the factory microphone set with no aftermarket microphone stuck anywhere!

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Pictured in this thread is the second one I’ve made, so far I’ve had no issues.

It’s worth noting that this is being done with Kenwood radios which use those basic microphones with 3.5mm jacks. I imagine most if not all other brands use the same style and so it should work for them as well. If however yours uses something else with a different connector, you’ll need to research if there is any reason for it. I doubt it, though.

Enjoy!
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 #392627  by M-Pressive
 
I need to find another UConnect mirror and do this in M-Pressive.

Much cleaner install!

Nice work
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 #392635  by M-Pressive
 
I ordered the cable.

Time to find a pigtail and mirror.
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 #392644  by M-Pressive
 
Found a mirror with pigtails included for $35 shipped on eBay last night!
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 #392645  by LUNAT1C
 
Hard to beat that!
 #393158  by bbb123
 
Cheaper at upullit yards but pinout includes power wires for microphone

You can find any connector pinout free online at connectors.dcctools.com

They used that radio on pci bus dodge/Chrysler/jeep starting in 2004 and on can bus vehicles ending with the 2018 grand caravan

Most also have auto dim


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 #393159  by bbb123
 
Here is the pinout from connectors.dcctools.com for 07 minivan

Cav Circuit Gauge Color Function
1 -
2 -
3 -
4 X722 20 BK/LB MICROPHONE 2 IN (+)
5 -
6 X712 20 BK/GY MICROPHONE 1 IN (+)
7 X793 20 DB IGNITION RUN/ACC SIGNAL
8 -
9 X730 20 BK/VT VOICE RECOGNITION/PHONE SWITCH SIGNAL
10 -
11 X835 20 BK SENSOR GROUND
12 X792 20 BK/WT MICROPHONE IN (-)


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 #393219  by 00R/T
 
I’m glad this thread got bumped because I hadn’t seen it before. I also hate the way the aftermarket microphones look so I decided to put a microphone mirror in the Mustang. I needed one with map lights because that’s where they’re located in the convertible, and the 200 convertible is the only car I found that had mics, auto dim, and lights. I found one at the yard last week, but ran into the same issue with the audio cable I bought. I’m going to grab one of those MicroCenter ones for sure!
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 #393794  by M-Pressive
 
My setup is soldered and ready for install.

Hopefully one night this week.
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 #393854  by TrepKing95
 
Can't believe it took me this long to find this how to! Guess I'll be making a trip to MicroCenter tomorrow to pick up a couple sets of supplies to do this on both my 300M, and my 2002 Grand Cherokee, both with the XTRONS "RB1 lookalike" head units.
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 #394132  by In-trepid
 
I am getting ready to hook up the mirror microphones to my Xtrons radio. The radio only has a microphone (+) and (-). The mirror ha two microphones in it. My question is: Can I hook both microphone (+) leads to the single microphone lead to the radio? should this work fine, or will it cause an impedance mismatch? Also, it is mentioned earlier in the thread that the microphones in the mirror are powered (amplified) units. Has anyone left the power to the mirror via pins 7 & 11 on the 12-pin mirror plug when installing this mod?
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 #394136  by LUNAT1C
 
I did not use those pins, only pins 4, 6, 12 are used in my setup. I'm not certain what 7 and 11 pertain to, though I have found various versions of these mirrors and some have additional sensors built into them. I assume some kind of rain-sensing wiper sensor, built into the windshield mount portion. Would be interesting to get a complete diagram of models with additional features to see what they go to.

Can't answer whether or not you can simply wire the two microphone positive leads to the one pole for the Xtrons, I have only ever used Kenwoods with 3-pin audio jacks. I would think they'd be somewhat sensitive if Chrysler wanted them to have separate + leads.
 #394188  by 00R/T
 
In-trepid wrote:I am getting ready to hook up the mirror microphones to my Xtrons radio. The radio only has a microphone (+) and (-). The mirror ha two microphones in it. My question is: Can I hook both microphone (+) leads to the single microphone lead to the radio? should this work fine, or will it cause an impedance mismatch? Also, it is mentioned earlier in the thread that the microphones in the mirror are powered (amplified) units. Has anyone left the power to the mirror via pins 7 & 11 on the 12-pin mirror plug when installing this mod?
I would avoid putting the mics in parallel. This typically doesn’t work well. Your best bet is to just use the left one.

I’m not sure if these mics are amplified or not. My hunch is that they are not, especially because they’ve switched away from the mirror mics to headliner mounted ones and those definitely aren’t. I have power running to the 200 mirror in my Mustang for the auto dim, but it doesn’t seem to make a difference with the microphone sensitivity.
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 #394199  by TrepKing95
 
I picked up a set of the Mic cables at Micro Center on my last visit; I'm also going to see if you can wire the 2 buttons on the mirror to the radio for additional functionality via the steering wheel control wires.
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 #394203  by LUNAT1C
 
I have some extra mirrors and connectors in my stash and may spend some time over winter to investigate if anything can be done with those buttons, but I suspect Byron is right and it's not as simple as connecting the pins to something that would operate a function. I suspect they send a signal to a specific PCB in one of the modules from the donor cars that we may not have. If you have the full OEM bluetooth setup, they should be able to work, but some reverse engineering may be necessary to perhaps get something like an Arduino to mimic what those modules might have done.

I'm just guessing of course, I studied mechanical engineering and physics, not electronics engineering. :lol:
 #394207  by 00R/T
 
LUNAT1C wrote:I have some extra mirrors and connectors in my stash and may spend some time over winter to investigate if anything can be done with those buttons, but I suspect Byron is right and it's not as simple as connecting the pins to something that would operate a function. I suspect they send a signal to a specific PCB in one of the modules from the donor cars that we may not have. If you have the full OEM bluetooth setup, they should be able to work, but some reverse engineering may be necessary to perhaps get something like an Arduino to mimic what those modules might have done.

I'm just guessing of course, I studied mechanical engineering and physics, not electronics engineering. :lol:
I’d be shocked if it wasn’t just resistor multiplexed between pins 9 and 11. That’s how pretty much every other switch module was implemented pre LIN bus.

I’d put an ohmmeter between those two pins and see what you get.
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 #394220  by bbb123
 
I killed a pci Uconnect Bluetooth module just hooking up a meter on resistance setting to those leads
I really wanted to duplicate the rare factory switch pod separate from the mirror but ended up concluding the output was NOT simple mux resistance and although mounting microphone without mirror was simple mounting switches without mirror was not at all an easy lift
Had many uconnect mirrors to play with and the switch output was not a meter measurable resistance unlike early and late cruise control switches and radio control switches which were mux resistance or open or closed on the two wires
It all started because my 98 TJ mirror button has straight parallel edges not suitable for a unconnected mirror plus it had temp and compass displayed on mirror


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