Examples of behavior which has already resulted in fines:
Opening fake deposit and credit card accounts, in customer names but without customer consent,  to meet employee cross-selling goals.

Retaliation against a whistleblower for reporting suspected bank, mail and wire fraud.

Charging consumers for unnecessary auto insurance, mortgage fees

Failure to issue GAP insurance refunds for consumers who paid off their car loan early

Failure to comply with Servicemembers Civil Relief Act (SCRA)

• failing to cap interest rate to limit servicemembers' obligations
• not disclosing active duty status to court prior to evictions
• repossessing servicemembers' automobiles without court orders

 
Misleading California investors, charities, and small businesses about the risk-level of auction-rate securities

More recent alleged scandals:
Sacramento Bee: "The city of Sacramento has filed a federal lawsuit against Wells Fargo alleging the banking giant steers African American and Latino borrowers into high-risk and high-cost mortgages."

KTLA in Los Angeles: "Hundreds of people had their homes foreclosed on because software used by Wells Fargo incorrectly denied them mortgage modifications."

NBC news: "Lawyers say they've found cases in 11 states in which Wells Fargo has wrongly claimed borrowers asked to pause mortgage payments during the COVID-19 pandemic" causing erroneous forbearance filings.