Although I rarely say this, I would recommend replacing them both. If you have an adjustable soldering iron, turn it up all the way when you solder the new LEDs in. If you don't have an adjustable iron, then get a 45+ watt handheld iron. The LEDs are OK being exposed to the ultra high heat, provided it isn't applied for all that much time. It's much worse to use low heat for a much longer period of time.