2008 RX350 AWD 216K miles

I live in Illinois. In our area we have to get an emissions test at a state facility to renew the plates. The current test just involves plugging into the OBD connector; no actual sniff test.

Mine just failed. The report says "This vehicle failed the OBD test because we were unable to communicate with the vehicle's OBD system. This is commonly caused by a damaged or corroded Date Link Connector (DLC) but it could be an indication of other problems in the vehicle's OBD system."

First things first: Is the DLC just the name of the OBD connector?

Secondly, is there some electronics that is just about OBD or does the connector simply talk to the engine computer?

I stopped at an Auto Zone on the way home and we used their OBD scanner. It showed no issues. I know it was talking to whatever it talks to because it picked up my VIN number. There has been no CE light or driveability issues. I realize some emissions things may not affect driveability but you'd think they'd throw a code. And total failure of the ECU would certainly be noticed.

Is there anything I should look for in terms of bad or loose connector? The OBD connector itself looks just fine.

I wonder if I should just get several OBD readouts, maybe buy my own, and go back, maybe to a different facility and say, look, 4 different OBD readers were able to talk to the OBD system so lets try again.

Battery has not been disconnected recently. But it is getting old; but I think if the voltage dropped too much during engine start to wipe out data their system would reject for lack of sufficient data since last battery disconnect.

Is there a difference between what their system talks to or a run of the mill OBD scanner? Also, regarding those, there are some that won't show codes that didn't result in a CE light and others that will.

 

Take it to a different shop, not uncommon for the issue to be with the test equipment and not the car. Of course if your battery is not doing the job replace it right away.

 

Tests are done by a state facility, not a private shop. I'll eventually have to go back to them although it can be a different facility or even a different lane at the same one.

BTW, if this is about the connector itself as the report says is a common cause I have to say that neither the first tester nor the second who came over did anything like unplug & replug or wiggle the connection, the common sense things people do when a bad connection is suspected.

 

If you suspect it's just the connector, and I would agree, then I suggest you simply gently scrape the metal contacts with a thin file.

They make "diamond files" for automotive connectors. But I think you can use anything thin and abrasive.
**Be Careful, of course. You don't want to spread the contacts, or push them in.**

"I stopped at an Auto Zone on the way home and we used their OBD scanner. It showed no issues. I know it was talking to whatever it talks to because it picked up my VIN number. There has been no CE light or driveability issues. I realize some emissions things may not affect driveability but you'd think they'd throw a code. And total failure of the ECU would certainly be noticed."

Maybe all it needed was a good scrape on the contacts. I don't imagine the guys working at these IL state facilities try hard or care enough to make things work.

 

Fellow IL resident here, I personally doubt it's your car if you have no CELs and it's running/idling fine. A new battery may or may not help, it's cheap insurance, I'd change it if it's due not because of this issue.

If you want a true test, you need a good/full OBD2 reader or full Toyota Techstream to read the emissions related readings (ex. A/F, O2, exhaust temps, etc) and see if they're within spec. I'd also try a different testing location if possible or bring a copy of a sample emissions reading and blame them, do not strike out 2 times (or more) or you'll have a bad time.

 

If you change your battery before your re-test you risk not having monitors complete and failing emission test for that reason. Go to another inspection station, it’s likely their machine or equipment, like a bad connection on their obd hook up module. I did NYS inspections for years, the NYVIP machines would have a similar problem at times. If you had a blown fuse for the obd connector it also may cause no communication, sometimes they share a fuse with a aux power outlet or cigarette lighter. Usually that doesn’t allow the small readers to read codes and check the monitors either though, which you stated we’re all able to read codes and check readiness monitors.
Frank

 

I'd say to replace the fuse for the obd2 port.........

 

Did you ever get your Lexus to pass OBD inspection?