[rasterman]

Corroded grounds, failing alt or both.

 

[rasterman]

It can, but it could also be another component unhappy with overvoltage. Bad grounds can fake out the alternator- cause it to give too little or too much power. Or both conditions at different times. Most electronics hate spiky dirty power, so this could be something else on the edge of frying as a result.

Either way, start with cleaning & tightening the grounds and then testing the alt output.