DTC Codes - How often do you check?

[KatDiesel]

With the ocasional post of DTC codes coming up, was just curious how often do most of you check for codes? Do you wait until the engine light comes on or just periodically cycle the ignition to check? I checked today out of curiosity since I have been modified for a while and don't baby it... ... . was kinda relieved to see P-done



So like I said was jsut curious what everyone else does? I don't need "advice" on the matter was just curious is all.



For those that may not know how to do this..... turn your ignition key on, off, on, off, on leaving it "on" this third time time (not starting the truck) then look at your odometer and it will flash codes there, it will say P-DONE when its finished or if you don't have any codes.

 

[Lurch]

You shouldn't get a code unless the engine light comes on.



Lurch

 

[Mschevey]

Codes can be there even with out light. I checked mine after I got it back from the dealer. (cold weather idle reflash) No light but the code I asked about was there.



Other than when I take it to the dealer, I don't check unless something catches my attentin. Ex. wait to start light staying on longer than usual. gauges act-up, etc.



My $. 02



Mike

 

[DGFoster]

I keep getting a 1693 code,I disconnect the battery and it goes away then comes back,but runs great.

 

[KatDiesel]

Originally posted by EKarr

You shouldn't get a code unless the engine light comes on.

I was in KC again so I couldn't respond. . and its already been said... but yes some codes are set without a check engine light coming on

 

[jtisdale]

Thats neat! Why didn't my dealer tell me about that? First it goes P PCU, then P 1694 Then P done. < Whats that mean? How do you know what different codes mean? Thanks!

 

[KatDiesel]

Originally posted by jtisdale

Thats neat! Why didn't my dealer tell me about that? First it goes P PCU, then P 1694 Then P done. < Whats that mean? How do you know what different codes mean? Thanks!

Most dealers prolly don't even know you can do it (the salesman).



P1694 - Fault in Companion Module



No CCD/J1850 message recieved from the powertrain control module-Aisin transmission





Have you had your truck reflashed ever? You get the list of codes out of the service manual. If ya don't have a manual then just post here and you'll get an answer. Or maybe someone will be nice enough to fax ya a list.

 

[jtisdale]

Thanks Mr. Kat. That was fast btw! Yes, they enabled the cold weather hi idle function. Does it need to be cleared right away, or can it wait till the next time I take it in (prolly 2-4 weeks)? Thanks again!

 

[KatDiesel]

Originally posted by jtisdale

Does it need to be cleared right away, or can it wait till the next time I take it in (prolly 2-4 weeks)? Thanks again!

It can wait, its nuthing major, they just left it when they reflashed you I would bet. So they should clear it no charge!

 

[icarus33]

I occasionally check mine just to see if anything new has popped up. Sometimes get a DTC programing error for the VP44, but that may be coming from the ECM remapping I have. I'm more focused now on the Generator Field Open DTC which I think is related to the batteries.

That code has just started creeping up again as the grid heaters are starting to get used a bit in the mornings. It takes a bit for the alternator to juice them up a bit, sometimes to where the check gauges light comes on after startup. I think this winter will be the death of these and time to make room for the Optimas.

I'm using the the software still from Alex Peper from obd-2 software



ic

 

[mongoose]

tried the on-off on-off on sequence with my 99 and it did not seem to work. all that would show up was the mileage. any suggestions?

 

[Mschevey]

You have to make sure it (dash) comes on and then turn it off. Timing took me about 2 or three tries to get down.



Otherwise it should work for you.





Mike

 

[KatDiesel]

Just thought I would float this back up..... in case someone doesn't know how to do it.



Man theres alot of catching up to do when your gone for a week!