comments:
Rude_Barracuda_129 posted on r/powerwheelsmods7w
Theres your problem you need to use flux to help the solder to adhere properly. Next time, buy some flux, put some flux on the terminal heat with iron then stick some solder to the terminal. Then put some flux on the end of the wire, heat with the iron and stick some solder on the wire. Then put some flux on the terminal that you soldered, then using the iron push the tinned wired against the terminal. Once its hot enough the solder will flow together and you're done. Or else you could just buy this Adapter Its not available to buy in Australia so I can't see the price.