Thread: how can I read more OBD data?

OBDII is a standard interface, and a possibility of car manufacturers to make their cars (at least in part) compatible. So you can just read the values that manufacturer implemented into OBDII layer.

On the other hand, every car has its own comminication interface (newer the car higher the possibility for CAN-bus).
That system is able to provide all the informations. Car (or brand)-dependent specific program is the keyword for you.
What car do you have?

I have Suzuki Grand Vitara 2006 & Toyota Corolla 2005.

is it hardware of software related? as far as I know almost all common OBD adaptors are based on the same chip, so the problem must be the software?

is there any reading material on this subject?

both cars are CAN bus so you would need something like ELM327 and software you get free is very limited ( you might want to look on eBay for some cool stuff ) or buy software if you can and it wont be cheap

my adaptor supports CAN .
can you recomend a software?

OBDII interface is a standard and working on the same way on every car implemented.
Car-specific thing talks to the computer on a different way.
It is similar to a man with a limited knowledge of a language. If you speak to him on the mother tongue, you can make a real conversation with him, but if you try to speak on a foreign language, you just receive words in a wrong order, if he understands you at all...
Me Tarzan, you Jane )

So, it depends MAINLY on software, but in some cases, it also COULD depend on hardware, but it is not toooooo serious (usually a different type of interface).

There are simple chips (eg. mcp2551) that convert CAN-signal into TTL (tx and rx) signal. Unfortunately, the speed is higher than a simple serial port could handle. Therefore, it is recommended to use the Universal Serial Bus (USB), or using a microchip that buffers the data stream.