It seems pretty obvious that there is a warrant out for you from what you have stated here. As I understand it, you were unaware of any "pending" case until you did a little checking. You need to get together with a good criminal defense attorney immediately, and do not speak with police without counsel present.
Your lending case may be a pending arrest warrant meaning you may be able to go into court and surrender and possibly get an OR release. This if course has many factors which it would depend on.
Elliot Zarabi www.FreeCriminalConsultation.com 213-612-7720 This answer does not constitute full legal advise. I do not know the full details of the case and therefore cannot make a full determination on your case or your answer. I always recommend speaking to an attorney in detail regarding your case.
Definitely. What happens is the Prosecuting Agency files the case and automatically issues a warrant. Some times law enforcement pick it up and try to arrest on it and some times they let it sit. If LAPD came to your house the very best thing to do is contact an attorney right now, locate the warrant and self surrender. We can handle all of that for you as quickly as you need it. If you get picked up and don't voluntarily surrender you increase the chances of staying in custody a bit longer. Im available any time.