need help truck over charging and no power with key on
 

my truck was over chargeing on my way home from work today at 18 volts shut truck off and now i turn the key on and no power on head lights and the batterys are full charged and fuses are good any ideas

check power and grounds first off, then check if fuses are getting power with key turned on. ( ign switch issues?) check main alt. fuse, good luck pt

sounds like the voltage regulator on the alternator took a dump and i dont know if the voltage being that high will fry anything or not

And with the statement above if it is the regulator is the problem it is inside the PCM but you can put a external one on. You have to keep PCM in the circuit and use the regulator in conjunction.