Toby uses a portable car battery pack to 'jump start' Nate's heart. Several errors are displayed. The voltage is too low and the current is uncontrolled to act as a defibrillator. The voltage spikes up on the meter when Toby touches it to the Nate's chest, this would only happen if there was a loose connection to the meter. It should display about 13 volts unless shorted or charging. When Toby touches the electrode to Nate's chest, he draws a spark. This would much higher voltage than the battery pack has available or a direct short to the other electrode. It wouldn't be hard to accept that a team of hackers has a AED (Automatic External Defibrillator) in their van or shop. This would have been a much better way to save Nate's life.