If you are working
with cars and trying to
diagnose at some point
you will need to
interface onboard
computer into computer.
For this reason you will
need a sort of interface.
Here we offer an OBD-II
to serial emulator. It
provides simple serial
TTL level voltages that
you will need to connect
to some sort of
converter to interface
it into RS232, USB or
Bluetooth
PCB layout with DB9
or OBD-II male
connector
The DB adapter version uses 9-pin D type connector to link up to vehicle's OBD-II J1962 connector. The pin out is De-facto a standard for OBD
cables. The cable available on eBay or AliExpress from many vendors.
J1962 Pin
Description
DB9F Pin
2
J1850 Bus +
7
5
Signal Ground
1
6
CAN High
3
7
K Line
4
10
J1850 Bus -
6
14
CAN Low
5
15
L Line
8
16
Vehicle Battery Positive
9
Features
TTL
level output 0 or 3.3v
CAN bus
J1850 bus
K bus
L bus