OBD2 wont read my NNBS

[iNFamas]

A mechanic told me that he cant get is OBD2 to read my nnbs Tahoe. He assured me that it was the car and his not scanner. I have done some wiring from the junction box under the dash. i read that it has ignition switched wires so i tapped into a few. My concern is a accidentally tapped into a wire that might deal with the OBD2 port. if anyone has info on the junction box and what it does and or what does what, that would be great. or any solutions ect.

 

[SunlitComet]

OBD2 ports have a 12 volt power terminal in the socket. Perhaps you killed it.

 

[Wake]

Do you have a 2006 model?

In 2006 GM switched to the CAN bus from the Class II data bus. My TechII won't ready my friends 06 Denali or my 07 Saturn unless I buy a CAN adapter for it.

So if you have an 06 and your scanner isn't CAN capable you won't get anything.

 

[Hummin24]

Had the same issue, turned out a penny had fallen into the cigarette lighter and shorted out. The OBDII is connected to the lower cig plug somehow.

 

[JennaBear]

Check the cig lighter fuse, under the hood.