Kirill Tulin

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11 years, 10 months ago.

OBDII CAN 29-bit 500kbs VOLVO

I would like to read the ambient temperature sensor data from Volvo's OBDII port and activate a small array of heating pads when temperature is around zero and below. Not familiar with obdii over 29-bit CAN frankly speaking. Could someone experienced please head me somewhere, please?!

3 Answers

Andrew Worsley
11 years, 9 months ago.

Do you have an oscilloscope - if so, can you see any activity between the CAN HI/LO pins on your OBDII port? And if you transmit something on the bus, do you see the same bit rate on the scope? I don't have any experience with OBDII (but do have CAN experience), nor any Volvo experience, but looks like there may be some Volvo models that used 11 bit CAN (standard frames) rather than 29 bit (extended frames) according to the list at http://pinoutsguide.com/CarElectronics/volvo_obd_connector_pinout.shtml - are you sure your car is using 29 bit IDs?

Accepted Answer

Thank you Andrew, it worked out with modified code of ECU reader. The bus is mixed for priority issues probably but my temp channel was 29-bit.

posted by Kirill Tulin 11 Apr 2013
Kirill Tulin
poster
11 years, 9 months ago.

Thank you it worked out!

X M
11 years, 9 months ago.

I have used SKpang Ecureader http://mbed.org/users/pangsk/code/ecu_reader/ with succes on an Audi S3 ( CAN BUS , 500Kbps ) Current version of SKpang ecu reader reads the following PIDs

#define ENGINE_COOLANT_TEMP 0x05
#define ENGINE_RPM          0x0C
#define VEHICLE_SPEED       0x0D
#define THROTTLE            0x11

You have to change these PID requests for the ones you need to read ... Details from http://en.wikipedia.org/wiki/OBD-II_PIDs

Hope this helps Regards , Christos

Hi Christos Thank you for you advice, but I tried it an unfortunately it never shows any data... Kirill

posted by Kirill Tulin 12 Mar 2013