P063d

[BHiggins]

Fault Code P063d

New to "Third Gen" forums, long time "First Gen" owner...

My 2008 is showing a P063D fault code which is "Generator Voltage Sense High", and the lightning bolt warning light is on (throttle control module?). However, even though the code says the voltage is high my volt gauge is showing low. I did a quick search for "P063D" but only came up with the definition. Anyone familiar with this problem? Fixes?

 

[MullenaxM]

The most common problem that will set this code is loose or corroded battery cable ends. Check the battery cables at the batteries and make sure they are clean and tight.



Mike Mullenax

 

[BHiggins]

I cleaned and tightened the battery terminals, the one positive on the driver's side was a little loose. Everything SEEMS to be ok now, time will tell. The truck only has 14k miles on it, I was not too happy to be having problems with it already. Again, HOPEFULLY that was it. Thanks.

 

[sag2]

This code (and ECM logic) was added to keep from burning things up in an overcharge situation when you had a bad connection causing high resistance. If you get an open circuit between the generator and the battery the output just keeps going up until something fries.

To keep this from happening this logic was added to compare battery voltage to generator output voltage. If the difference exceeds a certain level (probably around 1/4-1/2 volt) it assumes a bad connection and shuts down charging circuit.

 

[BHiggins]

Thanks again for the info... Everything seems to be ok after cleaning/tightening the terminals, we shall see.

 

[Jim Brewer]

Just had this fault code come up in my 2007 6.7L. I cleaned the terminals and it fixed the problem. The advice here easily just paid for my TDR subscription for a couple years at least. Thanks guys!