I searched on "C280 lock repair" and found 8 threads including this one:

http://www.peachparts.com/shopforum/showthread.php?t=149974&highlight=c280+lock+repair

There was also another thread by whunter that had a bunch of links in it. You could also do other similar searches such as "C230 lock repair", "lock fix" etc.

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1998 C230 330,000 miles (currently dead of second failed EIS, yours will fail too, turning you into the dealer's personal human cash machine)
1988 F150 144,000 miles (leaks all the colors of the rainbow)
Previous stars: 1981 Brava 210,000 miles, 1978 128 150,000 miles, 1977 B200 Van 175,000 miles, 1972 Vega (great, if rusty, car), 1972 Celica, 1986.5 Supra