Scan tool OBD2

[Katz427]

 looking too see if there is anyone, who has been thru this. A 2004 Ranger, the DMV can connect, but cannot send commands, too the Ranger. We have tried 2 different scan tools a $270 Innova, and a $$$$ Snap on , both can communicate with the Ranger. There are no codes. I tried 2 different  DMV inspection stations, one wireless,  and one with a cable connection. RESULTS were the same, they can connect, to the Ranger, they can get a signal, but cannot  access the various files, to check for codes..

[Mark Bliss]

I have not personally seen a case where the DMV unit won't communicate when other tools do.

But I would point out that the DMV unit should looking for two things in my understanding- Stored codes and passed monitors. No two-way communication or diagnostic capability needed.

States vary on their approach and standards. Mine uses an independent contractor and understanding/cooperation can be hit or miss. The testing operators just plug and run the test. I have in the past, had glitches occur and the operator seems able to override/fastrack me through. I have also gone to the office and explained situations that were problematic and they cooperatively worked it out.

Perhaps you could show test station admin, using the scan tool, that the vehicle has no stored codes and the monitors have run and passed? Worth a try.

[Mark Bliss]

Thinking more about this, I am curious-

The Snap-On scanner (I am not familiar with the other specifically) will have the option at one of the initial screens to go into OBD (global) or OBD (OE) mode.
Global mode (or generic mode) focuses on emissions and readiness monitor state, while the OE mode adds a bunch of diagnostic codes and features.
I was always told to think of this as "two ECU's in one" kind of working in parallel.

My point is, I would be curious enough to try and confirm that the scan tool communicates in both modes.
I have honestly never seen an ECU fail this way, but it strikes me as an outside possibility. I can say I have seen some (mostly older) ECU's fail with some pretty absurd symptoms. One specific ECU for example would work fine sometimes and then others totally lose its "mind"

[Katz427]

Well, Mark, the only thing left is the Ford dealer. Yes, we were able to read codes, none were stored, we also tried "enhanced" OBD2, no codes stored, and ran live data, everything looks good.  Dealer suggested the keys, but for this 2004, the Ranger doesn't have a chipped key.

[Mark Bliss]

Thanks for confirming that for my curiosity's sake.

And please, when the solution is found, update. I am always trying to gather diag. info.