MoTeC Global Forum

Hello, here to ask another question.

I am doing my own project to get a data from a car through OBD-II.

Car; Chevy Spark 2016,
Logger; SDL Sport.

Through OBD-II, what I want to log is just 2 things. RPM and speed.

From what I found; on C185 Motec Manager > New > OBD-II, there is already existing CAN comm setup for OBD so I mimic them. From the advice I got here before, I used ADL2 sport Motec Manager to make .CC7, which SDL Sport is able to read.

However, none of them - speed and RPM - did not work. Nothing recorded.
whole 3 weeks invested, but really can't find the answer...

But here is one thing I am doubting. On C185 Motec Manager > New > OBD-II > CAN Comm setup, it says;
Offset; 1 for ID; 410C(RPM), and click "Change" to go "Change Comms Channel" offset; 3 and length;2.

Since RPM uses 2 bytes, so the length 2 is correct,
but I am not really sure the offset value. Also why there is 2 different value for offset?

From what I know; I should hop 2 bytes to get the RPM only, so offset should be 2...?

What is the offset on the "identifier" and "change comms channel"? Are they different? What are they?

Well, not sure what you know.

Do you know how OBD-II works (request / response)? If not, this is a very useful reference:

https://en.wikipedia.org/wiki/OBD-II_PIDs

Do you have the MoTeC documentation on how their OBD-II CAN templates works? Your MoTeC dealer should be able to help you by providing that document.

Are you receiving any CAN OBD-II data on the SDL currently? (ie, is the baud rate correct, wiring ok).

I would post the complete CAN templates (TX and RX) you are using instead of screen shots if you want help.

Hello David,
Thanks for the reply.

Here is some answers what you asked.

Do I know how OBD-II works? ->
Probably. To get the data through OBD, I should request(Tx, 7DF CAN ID), and get a reply(Rx, 7E8 CAN ID). It is based on CAN protocol, consist of 8 bytes of CAN Data, first is number of byte it contains, 2nd for Mode (01 - show current data, Tx / 41- show current data, Rx), 3rd for PID, 4th to 7th actual data, 8th unused.

Do I have a Motec CAN comms Documentation? ->
No. The SDL Sport currently I am using is borrowed from my friend, so I think my friend would have the document you said.

Am I having any CAN OBD-II data on SDL? ->
I believe I am not. Not getting any data from OBD, since nothing was showing on the display. RPM and vehicle speed were '0'. I throttled, but nothing happens for RPM, I moved the car, nothing happens on vehicle speed. But gauge cluster on my car was showing right value.

Is my CAN Bus is okay? ->
Yes, I tried other CAN based sensor, it tells me right data.

Is my wiring okay? ->
Yes, the test from CAN based sensor, wiring is fine,

Is my pin okay? ->
Using proper OBD pins (6, 14) for chevy.

Is my baud rate okay? ->
However, the baud rate you mentioned, I believe it is not able to change on SDL Sport Dash Manager... Unlike C185 dash manager has 500kbps, 1Mbps, etc...

For the full template, please have a look at the image below. I have captured everything possible.

And other captures

Another capture

I think you may be able to set the CAN baud rate in Online->Communications->Connection Setttings -- I don't have an SDL here to test with, but I seem to remember that there was a different method used to set the baud rate on the SDL/SDL3.