Originally Posted by justbob
Have Sunseeker class c - get 13.1 volts to the coach batteries from alternator and get 14.2 volts when on shorepower. Wondering if these are the normal expect values.
In my opinion, the alternator charging voltage should be higher than that. More like in the 13.6-14.2 volts range. Especially without any substantial loads on, like HVAC blower on higher speeds, headlamps on, etc...
EDIT: A lot of factors come into play though in the charging system output from the alternator: Load, Engine speed, Battery condition and how new a chassis it is becuase in real late model vehicles the computer has a lot of control over voltage output so it can control the amount of load the alternator is placing on the engine. END EDIT
The shore power voltage would appear to be exactly what I would expect when you first plug up and then it could/would subside some if you have a multi-stage charger in your convertor. Again, just my opinion.
I am not saying your alternator is bad, but I would definitely investigate further as that charging system output voltage seems on the low side and could very well be the beginning of an alternator getting weak or failing.