1993 Volvo 960 Engine problems

Dt: contact owns a 1993 volvo station wagon 960. While driving on the highway heard a loud noise, most of the lights on dashboard lit up. Vehicle was in traffic and the temperature hand did not rise. The contact continued to drive home. The thermostat broke. This caused the temperature hand not to rise. The next day went out to check under hood and basically found the serpentine belt off track. The contact put the serpentine belt back on the vehicle, then shut the vehicle off, and found that the spinning belt had idler pulley, belt pulley, and belt tensioner. The vehicle was then taken to a repair shop. The parts were ordered and then the vehicle was fixed.*Ak