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Need to rewire battery and lights. Thanks!. Update (10/05/2020)
Need to reconnect wires to battery, speaker and motherboard but I don’t know in what order. Thanks.
Try to strip the wires and press them up against battery, speaker and motherboard, with the batteries in, hopefully with experimentation in the order you’ll hear music from the toy, and you’ll know which wire goes to which place. Usually red and black wires go to the batteries, and the white wires attach to the speaker, but each case is different.