I was able to connect a scan tool to my 2001 Bravada about two weeks ago. Since then, the only thing I have done is replaced both front wheel bearing/hub assemblies. Now I can't connect, and I've used 3 different scan tools. All my fuses are intact (including the cigar lighter fuse) and I'm unsure where else to look. I was checking my transmission fluid today and found this connector but could not see anywhere within reach, a place to plug it in.



That is the passenger side rear corner of the engine compartment. Any ideas what that is for or if it is related to my OBD port issues? Thanks!

 

it may not be something that was being used. does the inside of the plug look clean, or all dirty and oxidized? if its the latter, then it probably was an extra. i cant see it causing a problem with the OBD II port.

 

Plug is clean, no dirt or anything.

 

I still can't connect to my OBD port. The cigarette lighter doesn't work but my fuse in the panel next to the steering wheel is good. Are there any other fuses or relays that are on this circuit?

 

Under the hood is a 20 amp fuse, I think number 13, check that. If not try jiggling the key in the on position while the obd is connected

 

looks like the air pump relay plug...does your sec. air inj. pump work? if not thats probably the reason.... should be a plug to match on the side of the pcm.... just a guess

 

At the data link connector, under the instrument panel, pin #16 should have an orange wire and it must have battery voltage at all times. It gets voltage from fuse #2 in the instrument panel fuse box. The black wire on pin #4 must show less than 5 ohms resistance to ground at all times. The black with white trace wire in pin #5 must also show less than 5 ohms resistance to ground at all times.

 

I checked the wiring behind the OBD port, resistance, and voltage on those wires and they are good/intact. I'm running out of ideas. I'm pretty sure this code is causing my Bravada to run like crap and I can't get the port to work to find out what it is.