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OBD II connector not working

102K views 18 replies 14 participants last post by  aemiseggerk33 
#1 · (Edited by Moderator)
Ok. Check engine light came on so I borrowed my brothers scan tool and the thing would not power itself thru the OBD II port and not link up to the car. Works fine for his maxima and his friends accord so I know it's not the tool.

I also went to Auto Zone thinking it was his tool but the Autozone guys crap would not connect either.

Also it seems If I jiggle the key it'll power on but only for a split second. I say it seems cuz it looks totally random. Sometimes I jiggle and get life......others, I get nothing so I don't know if I'm crazy or what.

The fat auto zone dude that I reckon knows crap 'bout cars said my computer is bad. Then I told him bout the ignition switch and he said "could be that too."

It seems the ignition switch would be a culprit since I had some similar issues with a Jetta I had and it was the switch.

Please help!!!!
Am I the only one with this problem? I still have to look at the connectors under the dash and make sure they are all tight.

I think I have a mis-fire cuz the truck idles like crap and is drinking gas like its 50 cents a gallon.:bonk:

Wife started a new job far away so had to get a dollar menu dinner today and save money for gas for the week for her.
 
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#7 · (Edited)
If it wasn't for it working intermittently when you jiggle the key, I'd say fuse.
That intermittent action sounds more like the ignition switch, as mentioned
already.

That being said, it won't cost you anything to check the fuse. Some members
here have had problems with loose fuse block connections, though jiggling
the ignition wouldn't affect that.

As far as the gas mileage, how many miles on your truck? Ever cleaned the
throttle body? Cleaning itself may not do much for mpg from a strictly
mechanical point of view, but the improvement in driveablility/response can
result in better overall mpg.

Good Luck!

Chris
 
#8 · (Edited)
That was it guys. 20 amp midi fuse blown. I think it was #13 in the fuse box under the hood.

Later I'll get another fuse at autozone and go back to the same guy that said my computer was fried. Clown.

I owe ya'll a few beers.:thx

Yeah....the jiggling threw me for a loop. Like i said "it seemed" to be that. I knew i was just going nuts. Wierd coincidence.
 
#12 ·
Thanks again

Just ran into the same problem. A bluetooth OBD II connector would not work in my Trailblazer, but connected to my wife's Audi just fine. Found your solution, swapped the 20 AMP for the cig lighter with the one for the rear washer pump just to see and it powered right up!

Keep up the good work, everyone and I hope to contribute now that I am registered.

Cheers!

:thx
 
#14 ·
Youtube video of the blown fuse #13, 20A under hood

Glad I found this thread. :thx

The OBD II and Cigarette Lighter is powered by a 20Amp fuse #13 under the hood, by the battery, labeled "Cigar" :duh:

Google: "Trailblazer/Envoy - can't read codes - code reader won't turn on" for the Youtube video :hail:
 
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