I have a smart dc dc12/12/18 charging a lithium battery. Until today everything has worked fine. today the charger is not turning on, it is showing an input voltage of 12.4 on the app, have checked the voltage with a meter on the input terminals and it reads 14v the same as the van battery. If I turn the engine sense of in the app the charger turns on. Is it possible to reset the unit input voltage via the app. I can’t find the manual as we are away at the moment?