Weird OBD-II connectivity issue

[alia176]

Alright fellas, this one got me stumped. I wanted to pull the DTC today and fired up the Techstream. It connected to the vehicle but pulled no codes even though the CEL is on.

So, I connected up the Scangauge and voila, pulled up the DTCs. I was able to clear the codes.

Any idea what happened?

 

[Bumbo]

Perhaps you had a OBD negotiation issue?

Around that 2003-2005 year there were some changes from ISO vs CAN protocols.

I've seen funny activity because of it... specifically I have actually had a Scanguage dump zero point calibration on my 4Runner when trying to negotiate that protocol.

Just something to consider... I force the ISO protocol before connecting a device to my 2004 to prevent communication issues.

 

[alia176]

Perhaps you had a OBD negotiation issue?

Around that 2003-2005 year there were some changes from ISO vs CAN protocols.

I've seen funny activity because of it... specifically I have actually had a Scanguage dump zero point calibration on my 4Runner when trying to negotiate that protocol.

Just something to consider... I force the ISO protocol before connecting a device to my 2004 to prevent communication issues.

What surprised me was that I was able to connect to my vehicle with the same laptop, same cable and same software previously so I'm not sure what's the deal now.

Oh well!

 

[jrm]

Only time i had something

like that happen it was after i pulled the battery cable off to reset the ECU..