Must be Xmas time. I figured out the issue with the famous key fob problem of it loosing sync with the cars. Turns out it's a problem with one of the chips coming detached from the circuit board.
When you open the key fob with the board facing you, look near the top right hand corner. There's a rectangle shaped chip, check the prongs. I checked mines both times when each of my remotes wouldn't keep sync with the car, each time it was loose.
I resolder it or you can even use permanent glue between the chip & board to hold it firm if you're not comfortable with soldering. Make sure the prongs have a good connection. Sorry that I haven't taken any pics, but it's pretty much straight forward.
Yeah, I know my atar is big, but I put it in at normal size & it keeps blowing up to the huge size. Yeah, I've resized it, lower resolution. I'll play with it some more later when time permits.
That would make sense... I just took mine apart and studied the circuit. It appears that one of the battery (+) legs goes up to the two legs on that chip, through the chip, then down to two pins on the main chip.
Maybe that is a memory feature of some kind? I think the FOB's have a rolling code, so maybe this is what keeps track of the codes as it rolls over?!?!
I just took my FOB down to the lab and hit those points with some solder. If it works, I'll report back.
I had been having problems with my 1999 fob for some time. Replaced the battery and still no improvement. About every day I had to resync the fob in order to get it to work. After reading this post, I opened the fob and examined the chip connections but could not see that they were actually loose. Some days later I decided to go ahead and try the repair described in this post. The fob now works perfectly. Not only does it retain sync, but even the slightest tap of the fob buttons brings an instant response. If you are experiencing problems with your older key fob, give this a try.
No way in hell could I solder that. I don't have the steadiest of hands.
It's actually quite easy. It took me about 2 minutes to do it. It is easier if you first remove the rubber gasket surrounding the circuit board. Just use a sharp tip soldering iron and barely wet the tip with fresh solder before touching the 4 chip connection point.