I'm thinking my charger is going, or gone bad. I'm running A/H soda , 1 tablespoon per gallon, in a 30 gallon garbage can. 2 parallel 10 gauge SS plates. Shumacher se4225 set to 20 amps. It just doesn't seem to work like it used to. FWIW, it never, even when new, showed 20 amps, at best probably 10, no matter what I was cleaning. Now it shows about 2 amps. Even if I turn the dial to 60 amps, the meter doesn't change. I cleaned all the connections, and no difference. Is there a way to check the performance? With no load, the voltage reads 13.5 V