How do I determine diodes from SMD markings?

[lukes]

My parents have a pool controller (Pentair Intellitouch) where the RS485 transceivers were blown from an indirect lighting strike.  This is the second time this has happened and we don't want to pay $500 for a new board so I am going to try an solder on new Maxim MAX1483 RS-485 transceivers to see if that fixes it.  The weird thing is the "A" line of the two transceivers are tied together and to a diode, the same is true for the "B" line to the other diode.  The other side of each diode is tied to ground. The are components appear to be diodes, the multimeter thinks are didoes in diode mode.  The silkscreen of "V1" and "V2" made me think they are MOV but would that read in diode mode on the multimeter?  I would like to replace them as well but don't know how to determine the specs of them and what type of diodes they are.

Any idea how I can determine what the specs are for these diodes from the markings on the chips?
Line 1: P03A
Line 2: 4AHS5

See attached pictures as well

[Miti]

P03A is actually what you're looking for, no translation is needed. It is a SIDACtor protection thyristor. Just google it.

[lukes]

Thanks Miti!  I did a google search and was getting a lot of noise but couldn't narrow down exactly the part, one I typed P03A thyristor I was able to find the exact part.