No communication through OBD connector

[JB Miller]

My 00 gp gt has been running really strange. The gas mileage is very poor maybe 9.5mpg or so. There is power in pin 9 and the ground pins 405 appear good. There also is a slight knock at startup but the biggest issue is the lack of communication tru the OBD. Has anyone else had this problem or can give me some insight on what I should do?

[FoSHO99]

What are using to hook up to the OBD2?

[JB Miller]

A genesis 3.0 and a snap on was used and it failed to communicate with either.

[GeddyLee]

Moved to a more correct area.

[JB Miller]

Anyone?

[minichopper6hp]

does it power up the obd2 scanner? or just not communicate?

[JB Miller]

Yes it senses the cable and machine and that the key is turned on. The scanner said no communication check fuses, yet all the lights on the dash are working fine.

[gotboost3]

horn fuse! try that gm wired they're obd II in with the horn fuse see if your horn works...i had this same problem once in another pontiac...stupid gm people decided to wire shyt retarted lemme know if that works

[JB Miller]

I just tried my horn n it works fine so idk

[02grandprix]

try replacing you cigarette lighter fuse, that also runs ob2 port. Make sure next time you plug in your scanner first then turn the ignition key on, if not it may blow the fuse again. hopefully that is your problem man.

[minichopper6hp]

yea mine was cigarette lighter fuse lol but it wouldnt power up the scanner for me, so thats how i knew.

[JB Miller]

Both my cigarette lighters work so that couldnt be it. I think it may b a wire short somewhere. Now the problem is i need to find it in the miles of different wires.

[JB Miller]

So i went thru emissions today and obviously it didnt communicate so it didnt pass. But they told me it most likely has something to do with the wiring in the alpine stereo i have in it. But idk anything abt the wiring where should I start? ground wire?