hey 6.7 owners!..just wondering, when I turn my key on to start up in the morning I always push the exhaust brake button on.. one day it didnt come on while cold so I backed out of my driveway drove down the block & the exhaust brake worked fine..parked it & let it idle with button on & it stayed on for warm up like it should..just wondering why it didnt come on right away..it used to come on at start up.. .....

 

Its a computer.. who knows. I have the odd time where that happens to me too. No codes or anything with it.

 

hey thanks dog......its no big deal..it works fine....

 

I've noticed my truck doing this too. I think it has to do with the ambient air temperature, I've read that the warm-up feature doesn't work if the air temp. is more than 60 degrees. I've noticed that the outside air temp. drops a few degrees when I first start driving, maybe that explains it not working at first..?