Charles Pic will step aside for the experienced Finn in the opening session at Suzuka later this week.
Kovalainen has remained part of the Caterham line-up this season after losing his race seat at the end of 2012.
He has already driven in Friday practice in Bahrain, Spain and Belgium.
Caterham chief Tony Fernandes admitted in Singapore last month that Kovalainen was in contention for a return to race duties in 2014.
"It is no secret that I am close to Heikki and I have a lot of time for him, so let's see," Fernandes replied when asked by AUTOSPORT about Kovalainen's prospects.
Kovalainen had previously emphasised that while he was desperate to return to the grid next season, he was not willing to bring sponsorship to a team in order to do so.
"The fact is that I will not bring money, everyone knows that, and if that's going to be an obstacle again then it's out of my hands," he said.
"I'll try to find other ways, and I'll try to convince people based on another way, purely on performance and the things that I do and how I do things.
"Whether that will work or not I don't know."