I have a P0300 Random misfire code on my 2002 S4. The car is running fine now and I want to reset/clear the CEL to see if it comes back before I have any diagnostic work done. How can I do this at the OBD connector? Are there 2 pins I can short together? If so whihc are they?

Thanks.

 

If I'm not mistaken, the vehicle diagnostics system is on a bus called CAN which stands for Controlled Area Network (or you'll see it listed as Controller Area Network which is also commonly used).

The bus protocol or format of the signal requires there to be specific 'messages' sent to the various devices on the CAN Network and to send those messages such as, 'clear error code', you have to use an external device to initiate the message.

Shorting any pins on the connector will do one of two things: set more codes or possibly blow a fuse. There are power, ground and a CAN+ and CAN- pin on the connector and if you short the CAN pins together or to power or ground independently, error codes can be set in more than one device on the CAN bus. Bottom line --> go to an Auto Zone store and ask the guy at the counter if he'll clear your code for you. Auto Zone does this for free.

 

Thanks, I ordered a Vag Com device to read and clear the codes since it appears I will get some use of it. I have been to two Auto Zones and they boath said they could not do it, I know that is BS but they would not do it.... So I'll do it myself. Thanks for the response.

 

AutoZone must have changed their web site. This spring, they were offering free code reading. I went back to their site to see if I could find it and I can't find that offer anywhere now.

Getting yourself a device is easier anyway and now you can not only read your own codes but you can help your friends and family too!

Good luck!

 

Yeah, I meant to say that they won't clear the code. They read it for me, but both stores said they could not clear Audi/VW codes. Whatever. I'll do it myself soon.

 

I didn't try the battery method. I bought a Autel VAG305 from yellow*_*stone on ebay. $33 including shipping from China. Worked perfectly. Cleared my misfire codes and they have not come back since. Good luck.

 

A4 Cab, 2004, gas guage reads erratic, sensor in tank reads fine on scanner? What do I check next?