I have P063D code on my 2008 6.7 mega cab....I have brand 2 new batteries and alternator...what else causes this code? Any help would be awesome. thanks

 

I wish you luck in finding the answer to your code problem...This board was once a beehive of activity where suggestions and comments were willingly forthcoming...It's been my recent experience that few seem to come forth to help with answers or even opinions anymore, even though there seem to be many viewers for each post...It seems a sad end to a once useful forum......Ben

 

I have the same problem going on now. Good batteries, new alternator. I had to get an airbag recall done and on the way to the dealer the cel came on with the code P063D. The voltage gauge was slowly moving towards the low side. I made it to the dealer but they had to jump start the truck.

The dealer said they had to replace the driver side positive cable and that fixed it for a day. I’m not sure if I want to take it back to them as they are going to say I need to keep replacing parts until it is fixed. At $800 a visit, I’m not happy with the dealer.

From my understanding, the ECM reads voltage and then turns on or off the alternator. So the possible problems can be batteries, battery cables, the two wires coming from the alternator going to the ECM, or the ECM.

How fo you know it is the ECM? That is a very expensive part.

 

I did the same thing replaced batteries and alternator all at once problem went away for 2 days now I started the truck it's at 12.3 volts telling me to check guages and has 036d code was wondering if you resolved your problem ? I have an 09 6.7