1998 W210 Door lock problems

[lp1raddad]

For about the last 3 months, there are times when I hit a bump, or turn with someone in the passenger seat that my doors will unlock and then relock, all in about 1 second. This can happen many times in a day, then go for several days and not happen. Its worse when it is really cold, seems to happen less when warm. Any ideas??

Thanks,

LP