You made what amounts to a parallel path. You can probably just leave it alone
If you learn how shunts work, that is how tiny meters measure large current. You take a sensitive meter, would would be "exploded" by a few microamps or milliamps, and put it in parallel with a large conductor. The conductor carries a majority of the load and it is carefully calibrated to allow "just the right" amount of current through the meter to operate.
If your ammeter was less amps full scale, say, 1 or 10 instead of 30-40A, and the shunt was smaller, say no 12 instead of "whatever," the ammeter would still show some activity
In fact, in the early 70's, when Ma FINALLY improved the ammeter situation with the "big boats" they did just THAT. Used a charge wire with no "full current" ammeter. Then used a small scale, sensitive meter, and hooked the meter leads up to the big wire "in the harness" so that the harness wire ITSELF made the meter shunt
GM, Ford, Chrysler, all did this same deal
