Let me be clear. the Battery Charge section of the Battery Charger is working fine. It is charging at 12 V. at 2,10, 20 amps. The section that puts out voltage to the 12 V. Muffin fan stop-ed working so I found a small step down adapter that is rated at 12 V. to power the cooling fan for the Charger.The adapter is putting out 17.V How long will the fan last at this Voltage? I ran it for five minutes and measured it with a I. R. gun and it was not over heating.Thanks Again, Bill 84 Westy