There are sealed conponents within the battery housing (same as the eCVT) that can fail and the only solution is replacement of the entire unit. A simple shorted or defective Fan in the housing would call for battery replacement.

Also, the HV battery is the only way to start the FEH, and Everest didn't indicate if he had any trouble lights or codes. If the MMH went EV when this ocurred, it was all over anyway. I would like to know if there were any trouble lights or messages on the dash.

GaryG