M1330 time of day clock has stoped

I just go used M1330 from ebay and had to replace touchpad. Now when I got the laptop it had time of day clock has stoped i got new cmos battery and now it seems to reboot and power on fine without the error unless I remove ac addapter and battery and the next boot I get the error message. I also noticed that sometime my laptop does not keep time. One time it want to sleep over night and it lost a day. Does anyne knows location of real time clock on m1330 motherboard it must be close to battery or memory. Does the error means that realtime clock is bad or there is broken in solder ? Or other options that there other bad part. ?