O.k so my engine light comes on the other day and i drive truck with no problems. I stop by dealer today and they say no problem we need it for a couple of hours to look at. I pick up a couple of hours later and i ask what was wrong. Dealer says update codes and i say will it happen again? he says they come out with update codes now and again and light will come back on. HOW THE HELL DOES MY TRUCK KNOW WHEN THEY COME OUT WITH UPDATE CODES???

 

he's full of crap. the light came on, they happen to have an updated flash from DC that takes care of certain nuisance codes.
if the light comes on again. turn the key on and off 3 times(not start) and back to on. read the odometer. it will list the codes. the will be a P and 4 numbers, example P0191
then come back to the board with the code

 

I actually did a search on this site before i went. I did the key thing and the only thing that came up was-------. I hate when dealers do stupid stuff like that!

 

You must have a 6.7

Mine does the same thing when you do the key trick.

It --------- out for 5 seconds and then says done.

Going in next week for the latest update....

 

I think in 06 when the CAN-program came standard our trucks they took the key on three times out. My father in-law's 06 would not show any codes when he tried the key on three times.

So, to read codes on model year trucks 02-05 you can use the key on three times, but to read codes on model year trucks 06-present with CAN-ECM use a CAN code scanner at your local parts store.

Shawn

 

I can get them on my o6 with no problems