I've had all four lights changed on my mirrors recently. 3 of the four changed under warranty, (warranty being 60,000km. ) and the fourth light died just after the warranty was up, so the dealer did a 50/50 with me on parts and labour to change it. Looks like the problem was water that created corrosion, I could see rust stains on all of them. hopefully these were installed properly and i don't have to worry about any future issues. BTW - you just have to pop out the lower mirror to expose the screws to change out the light, or so the mechanic said! goood luck.