An employee checks an exchanged Samsung Electronics' Galaxy Note 7 at company's headquarters in Seoul, Oct. 13, 2016. REUTERS/Kim Hong-Ji

Samsung Electronics has finally completed its investigation into why its 2016 flagship device, the Galaxy Note 7, kept overheating and catching fire. And according to a source who spoke to Reuters, it was mainly a fault with the battery.

The source told the news agency Monday the official announcement of the investigation’s results will likely be made Jan. 23, a day before the company announced its financial results for the fourth quarter. While the fiasco with the Note 7 has cost Samsung an estimated $5 billion, the company seems to have largely escaped from any long-term damage to its brand and reputation.

However, it will have to convince prospective buyers of its upcoming flagship devices, including the Galaxy S8, which is likely to be launched in the first half of 2017. The company will need to explain to consumers and investors alike why the Note 7 had the problems it did, and why the same problem will not recur in future smartphones it builds.

“They’ve got to make sure they come clean and they’ve got to reassure buyers as to why this won’t happen again,” Bryan Ma, a Singapore-based analyst for researcher IDC, told Reuters, adding: “To me, it’d be surprising if they said it was a supplier issue.”

And the company seems to already be promoting the Galaxy S8, even though it hasn’t named it explicitly in promotional videos for its new AMOLED panels.