When we activate cluster diagnostic mode one of things we can see from there is list of DTC codes. While ago I was getting DTC5284 code (oil pressure switch failure) on my '02HD so I inquired around and I was told that is "normal" because test is started when engine is not running so there is no oil pressure. That makes sense and I would have left it at that if it weren't that I have found at least two persons that reported they had DTCNONE under same conditions. That was enough of an exception for me to ask Galpin Ford to look into it while they were looking at my other issues. They came back telling me that code is OK and they could not explain why some people have DTCNONE. Even though they told computer to clear any error codes (at least that's what they todl me) DTC5284 remained on cluster. Shortly after, when I was at Earl's Automotive, Earl hooked up his scanner to my truck and, although cluster was showing DTC5284, scanner was not showing any errors.

Now this is where it gets interesting...

Recently I took my truck to different service. Among other things I asked them to look into DTC5284 because I was still curious why some people don't have it. I showed to Service Adviser code itself in front of my friend, and he later showed it to his technician. They told me same thing that Galpin told me, that DTC5284 on cluster is the way it is supposed to be. So, I took truck home and thinking nothing about it started it in cluster test mode so I can see what RPMs I am at when idling. That's when I noticed following:



Yup, you saw that right. My truck that had DTC5284 at moment of dropping it off at dealership (at least 3 persons can atest to that) all of the sudden doesn't have it anymore. It has DTCNONE, just like those two other guys reported for theirs.

So, I went back to dealership to ask them what they have done to get rid of DTC5284 code and if they can educate me on that, and they said "we didn't do anything, we didn't reset any codes or computer". They were as surprised as I was to see it gone.

So, can somebody clue me in what is going on?

If DTC5284 was always to be raised when we turn on our cluster test then we shouldn't have trucks that don't have it, right? And yet somehow we have at least 3 trucks (including mine) that prove opposite.

And if techs didn't do anything like they claim what made it go away just like that?

ZoranC

 

How do you activate the cluster diagnostic mode? If you advise, I will report my results. My truck now has 3,200 miles and has never been to a Ford dealer since I purchased it last August

 

Good tutorial with step-by-step and pics is here (please notice that although tutorial shows it on Mustang process is still same):

http://www.mustangworld.com/ourpics/fcar/dtcodes.htm

As I said, quite a number of people have DTC5284. However, that doesn't explain why they have it and some others don't, nor it explains why I don't have it anymore.

ZoranC

 

Thanks for the link. Very cool. I can't wait until my wife takes her '02 T-Bird out of storage to see if it also has these diagnostics. BTW my truck reports "NONE" for DTC codes.

 

Cool! That makes four trucks that have DTCNONE, with some of them that came out of factory that way, and some that had DTC5284 that somehow went away after visit to dealer. This definitely makes me wonder what is going on.

ZoranC