Richard Drew/Associated Press

JPMorgan Chase is pulling out its checkbook to help mend frayed relationships with the government.

But its new and conciliatory approach — a departure for the bank and its leader, Jamie Dimon, who generally has taken a hard line with the authorities — is yielding mixed results. Government officials, stung by the bank’s past displays of hubris, may drive up the price of settlements or resist the overtures altogether.

The hefty payouts started on Tuesday when JPMorgan struck a $410 million settlement with the nation’s top energy regulator, which had accused the bank of devising “manipulative schemes” to transform “money-losing power plants into powerful profit centers.” The agreement was a record fine for the Federal Energy Regulatory Commission, whose most recent settlement with a big bank totaled only $1.6 million.

JPMorgan is bracing for an even larger penalty stemming from shoddy mortgage securities it sold to the government. In a sign that JPMorgan is struggling to placate some authorities, people briefed on the matter said, a housing regulator recently rejected an offer the bank made to settle those claims.

While JPMorgan is likely to fight some cases, the bank is quietly courting officials from the Securities and Exchange Commission, which is investigating the bank’s multibillion-dollar trading loss in London last year, the people say. It is unclear whether the S.E.C. investigators are receptive to JPMorgan’s advances.

The bank’s new approach comes down, at least in part, to dollars and cents. While the settlements are expensive, they pale in comparison to the sort of legal bills that come with long — and embarrassing — legal battles.

Shannon Stapleton/Reuters

The conciliatory tack also reflects a growing recognition among bank executives that JPMorgan was swiftly losing credibility in Washington. At least eight federal agencies are investigating the bank, and some regulators have portrayed JPMorgan as something of a bully.

For example, regulators have accused the bank of resisting scrutiny of the $6 billion trading loss in London. That echoed claims from the energy regulator, which accused the bank of stonewalling its investigation.

The complaints have buffeted Mr. Dimon, JPMorgan’s chief executive, who was once known as Washington’s favorite banker. In a meeting in April, regulators from the Federal Reserve and the Office of the Comptroller of the Currency warned Mr. Dimon that they were losing patience with JPMorgan.

Since then, Mr. Dimon has taken a more contrite tone. Weeks after the scolding, people briefed on the matter said, Mr. Dimon took a rare step of convening a town-hall-style meeting with examiners stationed at the bank’s Park Avenue headquarters. While he did not apologize for past missteps, Mr. Dimon conveyed a willingness to respond to their concerns, according to the people briefed on the matter, who spoke on the condition of anonymity because the meetings were not public.

Mr. Dimon also met with the comptroller of the currency, Thomas J. Curry, to forge a direct relationship with one of his top regulators. In the meeting, people briefed on the matter said, Mr. Dimon told Mr. Curry to bring any concerns directly to senior management.

Mr. Dimon later apologized in a letter to shareholders for letting “our regulators down” and vowed to “do all the work necessary to complete the needed improvements.” The bank, executives note, committed resources to bolster internal controls, a measure that could help improve its frayed relationships with regulators.

Still, the outreach is a work in progress. Some regulators said they were hesitant to believe that the bank was truly reforming its ways, with one official describing the government’s reaction as “trust but verify.”

Mr. Dimon also cautioned shareholders that the bank would most likely face more federal enforcement actions in “the coming months.” Mr. Curry’s agency, for one, is considering an enforcement action against JPMorgan for using faulty documents in lawsuits against customers who fell behind on their credit card bills.

JPMorgan’s most costly case could be its battle with the government over billions of dollars in mortgages it sold to Fannie Mae and Freddie Mac, the government-controlled housing finance companies.

The Federal Housing Finance Agency, which oversees Fannie and Freddie, accused JPMorgan and 17 other banks of selling mortgage securities that later imploded.

Now that the Swiss bank UBS reached a settlement with the agency this month, JPMorgan is next in line for a court date. JPMorgan lawyers want to resolve the case before that point, according to the people briefed on the matter. Yet an accord is proving elusive. The housing regulator balked at JPMorgan’s initial offer to settle, a setback for the bank.

Manuel Balce Ceneta/Associated Press

JPMorgan had more success with the energy regulator. Even though it extracted the $410 million settlement on Tuesday, the regulator spared a senior bank executive, Blythe Masters, who investigators originally contended made “false and misleading statements under oath.”

In March, agency investigators said that they planned to recommend that the regulator hold Ms. Masters “individually liable,” a move that would have cast a shadow over her career on Wall Street, where she is well known for developing complex financial instruments. The decision to forgo individual charges against Ms. Masters and three of her employees was an abrupt reversal for the regulator, which did not accuse her of lying in its final order. It is also a major victory for Ms. Masters.

The accusations of market manipulation surfaced in a confidential commission document reviewed by The New York Times. The document, a warning that investigators would recommend that the agency pursue civil charges, outlined a pattern of illegal trading in the California and Michigan electricity markets.

Since the regulator’s findings surfaced, JPMorgan has defended Ms. Masters and the traders, disputing that “Blythe Masters or any employee lied or acted inappropriately in this matter.”

The accusations against JPMorgan originated from its rights to sell electricity from power plants that it acquired after the bank took over Bear Stearns in 2008.

The plants the bank inherited were outdated and inefficient. Still, the regulator said, traders in Houston found a workaround. To transform the power plants into profit generators, the agency said, JPMorgan’s traders adopted eight different “schemes” from September 2010 to June 2011.

The trading strategies offered electricity at prices that appeared falsely attractive to state energy authorities. The effort prompted authorities in California and Michigan to make excessive payments that helped drive up energy prices, the regulator said.

As part of the settlement on Tuesday, JPMorgan will pay a civil penalty of $285 million to the Treasury Department. JPMorgan will also pay $125 million in “unjust profits,” the regulator said.

Under the deal, the bank must also make annual reports to the commission for three years detailing its power business in the United States. While JPMorgan acknowledged the facts of the trading strategies, outlined in the settlement, the bank did not admit or deny wrongdoing.

For JPMorgan, which reported a record $6.5 billion in quarterly profits this month, the pact will hardly dent the bank’s bottom line. But the deal, a bank spokesman said, does help the bank “put this matter behind us.”