Check engine light on after replacing the battery.
New battery installed and the check engine light is on and will not go out. Attempted disconnecting the battery again. Still on. Would like to not have to take it to the dealer if possible. Any suggestions.
Goto local parts store and have them run an OBD 2 scan... Avoid the diagnostic fee many dealers charge these days(Which I understand with ABS and specialty readings but a basic OBD scanner isn't worth what most of them charge).
pull your ECM fuse or UNHOOK the neg battery cable for about 5 minutes and let the computer reset itself.
alternator problem,, but it possible that you have a bad fuse too.
Alternator won't cause the check engine light to come on, the battery light will come on.
mabe a short, bad relay, lord lots of things
Was the light on before you replaced the battery? How many miles are on this truck?
We Replaced the alternator not the battery the battery was good the old alternator was burning out the battery now the check engine lights back like it was before we put it in shop but it wasn't on when we picked it up from the shop. Suggestions?