I have a Macbook that I bought in summer 2007. When my battery does charge it works fine, but it's becoming quite bothersome to have to unplug and plug in my charger 50 times before it works (which isn't always the case). I wouldn't mind replacing a part to remedy this issue, but I can't figure out whats what. I've cleaned the contacts on both computers and chargers, and reset the SMC for both. I can't explain it, there is no sort of procedure, but if i keep repeatedly unattaching and reattaching the charger it seems to work. To quit rambling, basically whats going on now (and this is happening with both computers and chargers) if I unplug and plug in the charger and over and over again it will "hit" on one of the tries and start working. So, I tried plugging my charger in again and still nothing, and once again the same with my sisters. Now, after about another week, my sisters charger also stopped working. (no light of any kind, and my power preferences confirmed it wasn't establishing any connection whatsoever) My sister also has a similar aged MacBook and I tried her charger, which worked perfectly. So, about 3 weeks ago I tried plugging my charger into my MacBook, and it was totally unresponsive.
I've cross-referenced that data with iStat Pro, and it concurs. (Late 2008 Black MacBook)I'll start with adding that I've calibrated my battery AND downloaded Coconut Battery, which has determined after roughly 290 cycles my battery still operates at 97% efficiency.
I know Macbook Charger/Battery issues are not new, but I think I have a problem I've yet to see on any forum.