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stanleyhuangyc / ArduinoOBD

OBD-II library and sketches for Arduino
http://freematics.com
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Can't get a read from Pontiac Bonneville #6

Open gmas opened 10 years ago

gmas commented 10 years ago

On my 2002 Pontiac Bonneville, I can see that a connection is made to the OBD2 port but no DATA is received when requesting PIDs.

Here is some debug output (added huge timeout in desperate attempt): [7939]recvbuf init: [7939]OBD Y

[7940]wrote: [7940]0105

[34944]data response: [34945] [34945]NO DATA!! (this is in COBD::GetResult()) [34945]recovering

[36346]wrote: [36346]0105

This is probably not an issue with the OBD board since I have confirmed it works on a Toyota Camry but I'm hoping someone can help me shed some light on this..

George

gmas commented 10 years ago

I forgot to mention, the Arduino is getting power from USB, not the OBD board. Not sure if that can be the cause for empty readings..

WA4OSH commented 10 years ago

George, According to the Dr. Robot wiki page, http://www.dfrobot.com/wiki/index.php/OBDII_TTL_Adapter "Supporting CAN bus (used by most modern cars), KWP2000 and ISO9141-2 protocols"

Your Pontiac may be running the SAE J1850 VPW protocol.

There are two ways to check this. Look at the ODB-II connector of your car and see if the pins give you an idea. Read this: http://www.obdtester.com/obd2_protocols

Another way is to borrow an OBD2 diagnostics tool from a car parts store. O'Reilly's near my house ends their Innova 3100 out for a quick code check. While it does an auto-link, it tells you what protocol it found.