Hi,
I bought on ebay a fingerprint sensor, unfortunately the seller deliverd a different typ of sensor, wich has 6 red wires instead of a colored 4 pin. 
A photo in the auction is this one, all different pins but no reaction. And it has 7 pins. 
Does anyone have also this module and how it will be connected to the arduino?
Thanks in advance. 
The problem with buying on eBay, Aliexpress and most of the Chinese suppliers is you don't get support or documentation. Contact the seller. If they can't supply you with information, put it in your rating.
GND and 3.3V are labeled on the board at the programming pads so you can test continuity to identify those 2 pins. Use the IC datasheet to test continuity to the other pins of the connector. You probably won't damage TX and RX if you connect them backwards the first time, but if you are concerned, put a small (10-100 Ohm) resistor in series with each. That should prevent any damage.
The third pin from one edge of the connector is GND. The second from the other side is 3.3V.
You also have a GND field and a 3.3V field on the board.
Easy to measure wich way the connector is wired with the help of a DMM.
Leo..
Thank you all, I have tried some configurations, with the result that I burned a fingertip at the very hot chip.
But if I found a solution I will post it here, I am sure this module will be delivered to many other too.
hi, i just cant figure out what are the libraries suitable for this sensors. can u suggest me what is the best. Ive tried using adafruit fingerprint library but it uses pin 2 and 3 as data transmission although the sensor pins stated use for RX and TX connection. I kinda need this urgently due to im using this sensor for my college projects
It doesn't make sense to use a library intended for one type of device with another type of device, regardless of whether both devices are called "fingerprint sensors".
RX and TX suggest a serial connection, as does the seller's page. Try using a terminal program on a PC, with a USB-TTL serial adapter.
PC Interface: UART (TTL logic level) or USB2.0 / USB1.1
Communication baud rate (UART): (9600 ╳ N) bps where N = 1 ~ 12 (default value N = 6, ie 57600bps)
If you burned the IC, there is little chance it will work.
Hi. I recently purchased this very same fingerprint module and it has the exact same 6 red wires that are diplayed in the photo attached. I attempted to connect the pins to a set of male to male jumper cables but they do not fit. I am very confused as to how I can connect this module to an arduino uno r3 so if someone could help me out I would appreciate it a lot. Thanks 
You will have to use the red wires, after cutting off one connector and replacing it with one or more that fits the Arduino headers.
I use and like the Pololu system.
thanks for your info, i use this wiring with adafruit but doesn't work (to me) with any virtual serial port, using a Duemilanove doesn't work, with a Mega using the UART port "Serial1" (pins 18 and 19) instead of virtual "mySerial" works fine.
thanks again.
Hello Dear Friends I was loking for this sensor:
Is from synochip , they have some demo software with serial port.
You can download the demo here : http://www.synochip.com/en/index.php?m=download.tool
jesusisaaccs:
Hello Dear Friends I was loking for this sensor:Is from synochip , they have some demo software with serial port.
You can download the demo here : http://www.synochip.com/en/index.php?m=download.tool
Thanks for your help! and what are the connections? how i can connect the Fingerprint to my COM? it´s necessary put one FTDI?
Hi!
I've just received my new 6pin fingerprint sensor without any documentation.
So I was reading the posts in this forum and unfortunately, the pinout didn't work for me, so I had to look for another solution.
I've found this pearl:
It works like a charm.
Hope it helps! 
I have the same issue. I have 6 wires, red, white,black,blue,yellow and green. how do i connect it to the arduino? what are the other two wires for?
Hi erduino,
I also received the device with 7 pins, with same pin markings as you mentioned in the image and am stuck with it. did the "just 4 wires" mechanism worked for you for exact same device or you change it?
Hi annu2127,
yes only 4 wires needed. You need only V+, GND, TX and RX.
Here is a link pdf documentation for alll the fingerprint modules available:
Hi Need a small help i have used the same mentioned connection and it works fine for sometime and then my chip starts heating up. Is is some connection or wire problem ?? and secondly how to make this module work with 3.3 v because if i give v+ 3.3v it doesnt work. P.S( I am using Adafruit_fingerprint library which works )
Urgent need help
Please advice
Hello good people
Me too use this sensor to my project
I have no problem about the connection.
My problem is when my sketch run on serial port is run well just like tutorial
But when I powered with external power the sketch not respond and when I plug again the serial cable it's run well again
I have use adaptor 12.2A as my external power so I think I have no problem with undervoltage case
I have short the Rx(0) and TX(1) with 10K resistor too but no effect
My suspicion is this sensor not compatible with Arduino
I have used 2 sensor with same type
And change another Arduino board
Please kindly reply
