Signature is set to revive its aborted Formula 3 project in time for the end of the 2014 season, and hopes to contest the Macau Grand Prix.
The French team, which carried Edoardo Mortara to the 2010 Euro Series title and 2009 and '10 Macau glory, took a two-year sabbatical from the category before returning with Renault's new engine for 2014's pre-season tests.
But the disappointing performance of the powerplant prompted Oscar Tunjo to quit the team and Signature pulled out on the eve of the opening round, precipitating a last-minute deal with Mucke Motorsport for Tatiana Calderon.
Signature has redeployed its F3 staff - led by former Carlin engineer Brice Gaillardon - on the Formula E project it is running for Venturi Grand Prix, but has also restarted testing of the ORECA-built Renault engine.
Ex-Formula Renault racer Paul-Loup Chatin, who competes for Signature's frontrunning European Le Mans Series team, has been driving the F3 car.
Whether Signature will return with Renault power depends on progress made with the engine, and the team has hinted that a switch to an alternative supplier could be made.
Volkswagen, which the team represented as a works entrant earlier this decade, would be the favourite for a deal.
Renault Sport Technologies boss Patrice Ratti told AUTOSPORT: "We haven't finished analysing the engine so I cannot say anything about the future."
When asked whether he thought the Renault engine could race this year, Ratti added: "I don't know - we don't have much information so we're doing more testing."
Signature technical director Lionel Chevalier said: "We want to come back because F3 is in our blood - we love single-seaters, we love F3 and we have two cars in the workshop ready to race.
"We want to come back with a strong engine - if that's the Renault it's wonderful, but we wasted too much time and a lot of energy at the beginning of the year."