Not familiar with this model or brand. I pick up quite a few non working battery chargers at yard sales for usually a dollar each. The newer ones must be total garbage as the majority of times they appear to have not seen much service at all. Before they failed.

If the transformer is still good as they persist in using old fashion selenium rectifiers.

If they short they stink. On the smaller chargers I have purchased I have just bridged the old open selenium rectifiers with silicone diodes. The rectifier was always open so far.

Then I just usually give them away to anyone I think needs one. Up to the seventy five dollar new models it seems to always be the same thing. Only costs me a total of 1.30 or so with purchase to make them even better than when they last worked in total. Perhaps better than new even I suspect as the silicone rectifiers are not failure prone usually.

In Kerry's case I would first check to see if the transformer is still putting out ac. Plus the 110 volt input is present at the transformer. If not scrap it. Yet if it passes these tests anything else may be cheap to deal with.

Battery chargers in general are not complex. Also look up this model on the net to see what is the common failure in these battery chargers with the high rate boost function.

I base this on also seeing a lot of them over the years just sitting around but no longer working. I have never had a use for them so never explored them.