Freematics Forum

Hi,

Has anyone been able to get out other data than RPM and SPEED, from the ISO 9141-2 protocol? If yes, could you post an example of your code?
That'd be great - thanks!
-Aslak

I just received my OBD-II adapter for arduino and I am having issues initializing.

Car: 2001 Saab 9-3
Protocol: ISO 9141-2
Arduino: RoboRED (UNO)

I cannot even get the example RPM sketch to work. It doesn't seem to connect to the car. Used oscilloscope to verify arduino is transmitting, downloaded and added libraries successfully.

I can compile and upload the example code to my UNO just fine (no errors). After uploading, Rx light blinks about once/3 seconds if i keep the UNO connected to the computer. Once I disconnect and use other power source (from OBD-II adapter) it doesn't blink anymore, but scope shows it is still transmitting.

****** Does anyone have this same problem or the solution to it??? *******

Below is the example code I tried.


/*************************************************************************
* Sample sketch based on OBD-II library for Arduino
* Distributed under GPL v2.0
* Visit http://freematics.com for more information
* (C)2012-2014 Stanley Huang <stanleyhuangyc@gmail.com>
*************************************************************************/

#include <Arduino.h>
#include <Wire.h>
#include <OBD.h>

COBD obd;

void setup()
{
// we'll use the debug LED as output
pinMode(13, OUTPUT);
// start communication with OBD-II UART adapter
obd.begin();
// initiate OBD-II connection until success
while (!obd.init());
}

void loop()
{
int value;
if (obd.read(PID_RPM, value)) {
// RPM is successfully read and its value stored in variable 'value'
// light on LED when RPM exceeds 3000
digitalWrite(13, value > 3000 ? HIGH : LOW);
}
}

Car: 2001 Saab 9-3

Protocol: ISO 9141-2

Arduino: Uno (RoboRED)

Problem: Adapter will not initialize

Question: Do I have to modify the example (RPM) code for my given protocol (ISO 9141-2)? Does the adapter try all protocols when trying to initialize (obd.begin())?

ISO 9141-2 is actually not supported though it's declared in the OBD.h.

Is exist another adapter that supports protocol ISO 9141-2 please? (sorry for my english )

Many cheap ELM327 (or cloned ones) support ISO 9141-2. We just don't have time and motivation to improve our implementation since the protocol is used by fewer and fewer cars.

Hi is it possible add iso9142-2 protocol in the library? here is explained the difference of response
http://www.instructables.com/id/Low-Cos ... /?ALLSTEPS

Hello,

2 years later still no upgrade to get the OBD UART to work with ISO 9141-2 ?
It would be a great idea to get motivations because newer cars have a very rich dash bord unless the old cars are more interesting for ARDUINO OBD projects.

Regards

I would also like to see updates regarding this. Looking to make a digital gauge cluster for my 99 miata. Stanley, any help on this would be much appreciated.

Sorry to disappoint you but we will not spend any time on the support for any pre OBD-II era vehicles.