WASHINGTON - Wells Fargo WFC.N Chief Executive Tim Sloan is due to testify before the Senate Banking Committee on Oct. 3, sources familiar with the scheduled meeting said.Sloan is due to brief lawmakers on work to remediate the bank after a phony accounts scandal erupted last year and a more recent scandal involving unwanted auto insurance.Wells Fargo's business has been under pressure for the past year after the bank initially disclosed it had opened as many as 2.1 million accounts without customer authorization over several years.The ensuing scandal led to a company-wide review that turned up problems with other products, including auto and life insurance.Last month, Wells Fargo said the unauthorized accounts totaled as many as 3.5 million.Senator Elizabeth Warren in a CNBC interview on Tuesday again urged the Federal Reserve to hold Wells' board accountable following the fresh disclosure.Sloan's predecessor John Stumpf had also appeared before the Senate Banking Committee in September last year. (Reporting By Patrick Rucker in Washington and Aparajita Saxena in Bengaluru; Editing by Anil D'Silva) ((patrick.rucker@thomsonreuters.com; +202 354 5858; Reuters Messaging: patrick.rucker.reuters.com@reuters.net))