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G6 OBD2 mystery

3.8K views 4 replies 3 participants last post by  DAKEN08G6GXP  
#1 ·
Hey everyone, I am wondering if I could get some advice.

I have a 2006 Pontiac G6 base model 2.4 L 4-cylinder and I LOVE this car.

Small history: I bought this car in Aug 2021 from a guy off Facebook. I immediately took it to emissions the next day and it failed due to no communication.

Now: I am determined to get this car to pass. I need it to. I am very much an amateur at this, considering a week ago I didnt even know where my fuse boxes were.

What I have done thus far: The EVAP valve was replaced. Then I bought an OBD2 scanner. When I plug it in with the car on, it lights up, "reads" then spits "ERROR" at me. My check engine light is on so there's something wrong. Oddly enough the scanner I was using (Hyper Tough HT100 Code Reader - cheapo from walmart) said ERROR but when it ran the diagnostics in the app, it told me no engine problems detected, ready for emissions test. I replaced the fuse that controls the cigarette lighter as I read thats a common issue. I also replaced the battery as it was time for a new one. Check engine light went off. Drove around for a while, next day, the engine light was back on.

Days later I took it for an emissions test to see what they could tell me. All I got was "it didnt pass, scanner can't read."

I checked the OBD2 port with my multimeter and pin 16 is putting out 12.79V, which I read is good.

From what I am reading (and it's getting overwhelming but Im doing my best) there could be a multitude of things wrong.

Does anyone have any advice on things I can try before I dive deeper into the intimidating stuff (and franky stuff Im not understanding just yet?)

I appreciate it in advance as does the lovely Donatello (the G6 himself) :)
 
#2 ·
Welcome to the club and good troubleshooting.

Did you find this thread? https://www.g6ownersclub.com/thread...m/threads/2005-pontiac-g6-obd2-no-link-spliced-wire-need-help.53332/post-284168. There is a wiring diagram showing the OBD port connections running to the BCM. 12v is good. Did you try checking ground continuity to pin 4 and 5. A number of owners have found bad grounds. The other thread also mentions adding dielectric grease to the BCM connectors that may be worth a try.

Good luck with the fix.