Some 122,000 borrowers with Countrywide home-equity lines of credit, or HELOCs, received letters in January informing them that they could no longer withdraw funds from their lines. A few months later, thousands of customers of other major lenders — including Bank of America, J.P. Morgan Chase, Citibank, SunTrust, USAA, Wachovia, Washington Mutual and Wells Fargo — also received notice that their lines had been frozen or reduced.