Test it first. Looking for conduction on both primaries, and both secondarys, but NOT primary to secondary.
If your card blinks and then nothing happens after that then its likely a victim of a surge or lightning strike. Happens all the time, I have had to change a few NICs over the last 20 years or so when lightning hits the power lines or the house. Takes out the cable modem, the router, and the NICs hooked to it.
That ethernet card is SUPER simple. the DP83902 is a very common ethernet IC, at least it used to be. if the HALO transformers are still good, then you may need to change the ethernet IC itself. Matter of fact, I have a card in my SE/30 PDS slot that I had to heatgun off and change the IC from failure.
