charging system problem
my dads truck has a prob. basically he has a newer battery (within a year old) not sure what kind it is. his battery will go dead after he turns the parking lights on or something similar. the truck wont start back up. after he jumpstarts it and shuts it back off it will fire right back up. took both battery and alternator to parts store for their tests, said they were good. any ideas what the problem is? we were thinking voltage regulator.