After making some research on the internet I can't find the remote wiring for my Xperia Z3C. I need this remote to use my headphones when running and be able to control the music when the phone is in my back pack.

I don't want the microphone because I don't answer call when running.

Well so let's make some reverse engineering xD

Step 1: Let's Make Reverse Engineering

After connecting the phone to a switch and a potentiometer I've find the right resistor values to have the headset recognized without the microphone (30K)

A short circuit between ground and the microphone signal cause a "play/stop" function. Pushing it twice causes a "skip"

The volume can be increased with a 100 ohms resistor to ground and decreased with a 470 ohms resistor to the ground.

Here is the schematic I've made from the measurements.

Step 2: Let's Build the Remote (without Microphone)

to build it you need:

• some electronic skills xD
• soldering iron
• a bit of prototype board
• some tools like pliers, fil, copper wire
• three smd switches
• three resistors (30K, 470R, 100R)
• one 3.5mm 3 pins jack socket
• one 3.5mm 4 pins male jack with cable (from another unused remote or something like that)

start by placing the component on the prototype board to know the right dimentsion to cut.

outline the dimension with a pen and cut the PCB with a metal saw.
File down the edge of the PCB

Step 3: Soldering the Components

Start by the 3.5mm jack socket and add some solder on the joints to have a good mechanical strenght.

weld the three switches.

Step 4: Resistors Soldering

now take the three resistors and place them as follow:

the 30K at the middle (play/pause switch), the 470R at the left (VOL-) and the 100R at the right (VOL+)

use a little bit of thin tinned copper to help you to make the connections

Step 5: Find the Connectors Wiring

Use a multimeter to find the right wiring of your cable/socket

Step 6: Make the Headphone Right Connections

now we must connect the wires to their right places.
start by connecting the ground wire. this one is connected to the switches common.

Introduce the "HEADPHONE RIGHT" wire through the PCB and solder it in place

Step 7: Make the Headphone Left Connections

Now do the same for the "HEADPHONE LEFT" signal

Step 8: Now the Microphone Signal

Make the solder joint of the microphone signal

Step 9: Lock the Cable

Now using a thick tinned copper wire you can make a loop and twist the end to hold the cable in place.

Step 10: And Voila!

it's finished!

you can use hot glue, bi-component expoxy or a plastic casing to protect the remote control assembly.

when connected the remote is recognized and now I can control the volumedown / up / play with the switches :)

feel free if you have any question.

<p>Cool remote circuit.</p>
<p>Thanks :)<br></p>