Fortunately, he probably hasn't blown up the LEDs. Not on 1.2 volts.
It is possible to check them anyway.
Check their resistance with a miultimeter. If they are short circuited in both directions, they are blown up.
If they are not short circuited, wire them up to 5 volts via a 200 ohm resistor.
The + of the 5 volts should go to the resistor. The other side of the resistor goes to the
long lead of the LED
and the other lead of the LED goes to the -ve side of the 5 volt supply.For more information what is an ir light, please get in touch with us!