came up with code p0606 does anyone know what it is and what it means as far as repairing

 

Any mods to your truck? Possible PCM, check power and grounds to PCM is code stored or active?

 

I had this code on my truck a few times about a year ago. It was still on warranty the first couple and the dealer said that it was intermittent power to the ecm, probably from disconnecting batteries or boosting heavy loads (which I do at work pretty often in the winter). I checked all my battery posts and tightened them up some and it hasn't been back since. My code reader also said internal pcm error but the truck ran fine, never had any loss of power and it just went away. Those really are the best kind of fixes. I don't think I'd worry about it too much, clear the code and see if it comes back.