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

 

Dont know but i certainly would not worry about it.Its a computer..........

 

Oil pressure switch failure code is something that does need investigation when it is reported.

If we can not trust computer when it is reporting that failure something is amiss. And if nothing is amiss and I didn't have oil pressure switch failure then all of trucks should report same thing. They should all have DTC5284 or DTCNONE, not some one way and some other. That is enough to raise big question mark, and truck that had DTC5284 that didn't go away even after alleged computer reset but went away after "nothing" was done should make us even more curious. Either I did have oil pressure switch failure that nobody paid attention to for 9 months (even though I reported it) or I did not. If I did not have that failure and "nothing" was done that code would be still there. DTC code that was there for 9 months doesn't go away overnight just like that without anybody doing anything.

ZoranC

 

I've said this before, prolly 5-10 times, but I'll say it again

Disregard the diagnostic codes read through the cluster. Those codes are for the CLUSTER only. It does not read other modules, like the PCM. The only thing that cluster diag mode is good for is the digital tach and digital speedo (which goes past 140, don't ask me how I know, LOL).

 

Can you please elaborate? I don't see how one could have that code on cluster if there was no failure, nor how it would be there for 9 months and then just go away after visit to dealership without anyone doing anything?

Thanks in advance!

ZoranC

 

No offense but you are looking way too deep into this.If you did not have oil pressure,your Light WOULD come on and your guage WOULD drop to zero.If I was the computer in your truck ,i would say,"mind your own gauges and leave me alone". You have no need to worry about the codes on the digital cluster.......If you did,It wouldnt be no big secret how to do it.It would be in your manual or something

 

It also works as a good fuel guage

 

No offense taken and nah, I am not looking too deep into it, I just want to get logical explanation that is still missing.

I, just like almost everyone else on this board, am interested in knowing more about my truck and what is going on with it. If code was there and it went away I want to know why it was there and how it went away. I am entitled to know, no matter how small it is, I am its own owner afterall. It is my choice to want to know.

ZoranC

 

I had a 99 Mustang that I first found out about this feature (prolly cause it was the first year of the digital odometer...in the mustang atleast). And I would mess with the trouble codes everyonce and a while. There were a couple times where codes would show up and then drop off a little while later. I did have a couple issues with my car but some of the codes it spit out didnt add up to the "known" problems I had. So in short, you might have a problem and you might not. If you aren't noticing anything acting up (besides the gauge readout) and/or dont have a check engine light then I would just chalk it up as an unsolved mystery and toast to having a sweet truck thats runs great

 

However, truck is acting up and is not running great. Besides, even if truck was not having issues that it is having, I would still be very curious because logical part of me would tell me truck doesn't lose code that it had for 9 months just like that, and possibility of that happening on its own without human intervention while it is in the service is astronomically small, if not zero.

ZoranC