One of my FOB's stopped working, but after taking it apart and cleaning it good, it still didn't work. Yes, I tried a new battery. Yes my other FOB worked fine. New FOB's are certainly cheap enough, but taking it to the dealer to program as per the Factory Service Manual and using a Tech 2 is not. An internet search for alternate ways to program new ones mentions things like the instructions for a 2000, turning the key on and off 3 times, which won't work for a 1999. Another method mentions of jumpering pins 4 and 8 on the OBDII connector or looking for an unused 2 pin connector in the trunk. I'm not inclined to jumper pins on an OBDII connector without knowing more about exactly what pin 8 really is (pin 4 is a ground). After doing all this research, I remember seeing the re-synchronization method in the Factory Service Manual, which involves holding down the lock and unlock buttons at the same time for 7 seconds, and wait for it to unlock or lock the car. I stood maybe 5 feet behind the car and tried it and it worked! I'll report back if this fix works long term. I have no idea why it even needed this, but I have a feeling that I might end up resoldering the battery clip as described in this video:
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