CTB16PCG3 - VR4 & D2 fried by ants, what are they?

[DrWizard]

Some ants got into one of my controller boxes, and amongst other things, fried VR4 (voltage regulator) and D2 (diode) near the Data/IO/RJ45 connectors.  The controller powers up but does not communicate so I'm guessing this regulates voltage for the RS485 input/output.

The original lettering on the parts is now unreadable.  Can someone tell me what these part numbers are?

 

[TheDucks]

1 hour ago, DrWizard said:

Some ants got into one of my controller boxes, and amongst other things, fried VR4 (voltage regulator) and D2 (diode) near the Data/IO/RJ45 connectors.  The controller powers up but does not communicate so I'm guessing this regulates voltage for the RS485 input/output.

The original lettering on the parts is now unreadable.  Can someone tell me what these part numbers are?

 

What model (and version #)

[DrWizard]

CTB16PCG3 V5

I have several of them, and I examined my un-damaged ones and the part numbers on the V4 regulator on ALL of them are too faint to be read, even with a microscope.  The Mfr did a very poor job of etching the numbers on.

[TheDucks]

3 hours ago, DrWizard said:

CTB16PCG3 V5

I have several of them, and I examined my un-damaged ones and the part numbers on the V4 regulator on ALL of them are too faint to be read, even with a microscope.  The Mfr did a very poor job of etching the numbers on.

<Dang site dumped just as I posted my reply>

the VR is a 7805BG (surface mount), the D2 is not the same as in the Kit version (D1-3 were 1N4002)

I would be surprised if frying the 5V did not damage more than JUST the D2.  FWIW the other is a 7810 (powers the external accessory)

[DrWizard]

Really?  That just seems odd, does the microcontroller chip run on 5v or 3.3v?  Because as I mentioned, the controller powers up and the LED blinks, it's just not communicating.  And I'm fairly sure the VR4 regulator is toast.  I didn't witness any magic smoke escaping since I wasn't around when the ants got in but some black goo has oozed out of the bottom of it and the trace between it and D2 is melted.  Maybe the black goo is burnt ant?  Also, VR1 and VR2 have the heat sinks and are right beside the transformer and bridge rectifier so I would think one of those is the 7805.  VR4 and D2 are right below the RJ-45 jacks so I suspect VR4 more likely is the 7810 for the accessories and RS-485, particularly since RS-485 voltage spec is 7-12 volts (not 5).

I've already ordered some SN65LBC184P RS-485 transceiver chips in case that is bad.