Hartley wasn't particularly fast in the test with Venturi Racing and ended up crashing the car.
That appears to have culled his immediate plans in Formula E.
"For the moment nothing's clear, but I'm confident I'll be a in a good place next year," Hartley said. "I spoke to many different teams [in Formula E], I tested with Venturi, but I've also been speaking to Indycar teams, IMSA teams."
It has been well reported that Hartley has been in discussion with Ganassi Racing in Indycars and there is genuine interest from both parties of a fulltime drive alongside four-time series champ Dixon next season.
"I'd love to be in IndyCar and hopefully in the next weeks something will become clear," Hartley added. "I'm genuinely looking closely at IndyCar and it would be a new challenge.
"I'm excited about the challenge of the ovals if IndyCar comes to fruition."