I’m trying to use Sparkfun’s OBD-II-UART board (https://www.sparkfun.com/products/9555) to interface with a CAN network using a Raspberry pi 4.
Upon connecting to sudo screen /dev/ttyAMA0 and when I send the commands, I’m not able to get any response from the OBD-II-UART board.
Can anyone say why it is not communicating?
Connected correctly?
Can you send some photos showing how it’s connected?
Baud rates match?
yes i have connect correctly.
when I unplugged and replugged the DB9 connector, I received the startup message over the terminal.
What is that other board you have connected?
It sounds like it's communicating if you're receiving a message when the device is powered on.when I unplugged and replugged the DB9 connector, I received the startup message over the terminal.
its logic level shifter the output of the obd is 5v and raspberry pi gpio voltage is 3.3 so i used it.
yes its communicating but i am not able to send the command from the raspberry pi terminal.
Did you work on obd II uart and raspberry pi?
if so how did you communicate with two?
Your level shifter doesn’t have 5 volt and 3.3 volt power. Connect those and maybe it will work.
when i connect to db9 (obd port of the vehicle) i get only startup message over the terminal. in order to connect i need a level shifter.
to get response the obd module should be on.
Your level shifter doesn’t have 5 volt and 3.3 volt power, those are required for it to work properly.
I tried connecting it directly and its the same.
Did you work with raspberry pi and obd-ii?
No, I don’t have those parts.
Sorry.
Do have experience with OBD-ii modules?
Very little OBD-II experience unfortunately but lots of experience with TTL serial.
