I thought I might let everybody in on a little information I found out about changing your alternator. I ran into this when I changed my alternator on my 2005 Mazda 6 5spd. After replacing my battery we had a flicker in the dash lights so I decided to change the alternator. It was charging at 13.9 when i checked it that same day but I knew it would be going out. I bought a new alternator from Napa took it home swapped them out and was only getting 11.9 and it was dropping so I new the alternator was not charging. Put my old one back on and the same thing 11.9 and dropping. I took my car to a local shop who ran it through some tests and they told my alternator was shot, really already knew that but ok. They got me a new which I said I would put on to save myself some money. When I went to pick the car up he was telling me how I needed to do it and then he said "Make sure and use a memory saver"?????? Never heard of one he said you can get one at Schucks it plugs into your cigarette lighter and keeps the memory in the computer. If you don't when you put your new alternator on it will fry them everytime trying to relearn everything. Wen to Schucks they didn't have any stopped in at Autozone a young kid knew what I was talking about showed my what they had but then proceeded to tellm all you have to do is take a 9 volt battery, wire the cigarette plug in onto the 9 volt and it works the same way. I was hesitant but he had me talk to an older gentlemen working there that previously worked at a dealership and he verified the information. I said ok so I went home cut the plug off and wired it to a 9 volt swapped out my alternator and what do you know it worked. I looked all over this forum for anything that would tell me if there was something special I needed to do. Found a lot of information but nowhere did I see this little bit of information so when I found out I thought I would share it with everybody.