As an accountholder with Chase, I asked the bank earlier this year specifically about an affiliated bank in Mexico. Chase replied that they have none and that all ATMs in Mexico are out of Chase's network.
You can ask any Chase Bank representative in the United States and they will tell you that BanNorte is the affiliate bank in Mexico (You should notify Chase about using your debit/credit card to avoid any problems with withdrawing your money) just as Banco Santander is the affiliate bank for Bank of America in Mexico (and they don't charge ATM commission fees).
The Chase website doesn't show any branches outside the USA. You need to check with the staff at the branch you use about affiliate banks. If you want to use a credit or debit card in Mexico you should also let them know you plan to do that so you aren't hit with an automatic security hold.
