Check with meter in Diode or Resistance mode. One direction should read infinity, the other may be from 127 to 500 Ohms. If it is near zero ohms in either direction replace the chip. When shorted, it will read near zero in both directions.

Note: Sometimes even the Gate can also take a hit, and shorting Source or Drain.

With +[pos] on pins 1,2 or 3 and -[neg] on pin
5,6,7 or 8 the resistance should be more than 300 Ohms if it is less than that in both directions, replace.