Failed emissions, no ground at OBD2 port
#1
Senior Member
Certified GM nut
Thread Starter
I failed emissions, but not for the reasons I'd think (the new cam). Apparently the testing station couldn't get any voltage at the OBD port.
I knew my scanner worked earlier in the week, so I had the local AutoZone test it. Their Actron scanner, as I expected, worked. So I went back for a retest and td the shop the fuses were good and a handheld scanner worked. Same result.
I went to the shop that the lady at AutoZone recommended. The guy there was nice enough to quickly explore. He told me that handheld scanners run off their battery, while the state'* equipment runs off of the car'* power. He was able to get a solid 12-volt reading from the OBD plug, but no ground. (He also aborted the test so I wouldn't be out another $20.)
If the wires under the OBD plug and the ground busses look good, I guess I'm looking at a new set of (real GM) battery cables. Anything else to check?
#2
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The problem should lay between the OBD2 plug and the ground point. Either the ground point is corroded, clean it. The wire is broke, replace it, or the terminal in the OBD2 plug is loose, remove it and crimp it.
#3
Senior Member
Certified GM nut
Thread Starter
Now that I've had a chance to sit down and Google it, some guy on a Ford forum who had the same problem had his cigarette lighter fuse blown. I know my lighter fuse is not plugged in until I get around to fixing the shorting lighter.
I'm going to start digging into things tomorrow night. Can anyone with a FSM check the OBD schematic versus the cigarette lighter schematic? (My Haynes manual is less than helpful.)
I'm going to start digging into things tomorrow night. Can anyone with a FSM check the OBD schematic versus the cigarette lighter schematic? (My Haynes manual is less than helpful.)
#4
Retired
Replace the fuse, get it scanned again. Just don't place the lighter back into the socket. I had the same issue with my 2000 Blazer.
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#5
DINOSAURUS BOOSTUS
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Dan...next time he wants to replace the battery cables, please don't talk him out of it. Even if it'* not the issue. His cables.. Great..I just puked in my mouth again.
#6
Retired
What was that all about Bill?
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#8
Senior Member
Certified GM nut
Thread Starter
My positive cable could be GM Forum'* Halloween banner. I've got some money coming in and battery cables are on the list (after tires and emissions testing).
Not that I won't give my 100%-GM negative cable one last good scrubbing during all this.
Not that I won't give my 100%-GM negative cable one last good scrubbing during all this.
#9
DINOSAURUS BOOSTUS
Expert Gearhead
Lemme put it this way guys. Justin and I refused to touch it. A couple of us have redone it in the past out of necessity and said "Colin this needs to be swapped asap". He nods like he'* going to do it and each time you see his car you kinda wonder how it keeps starting.
#10
Retired
Ohhh! I see now.
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