"We head into the final race of the season looking for redemption after a disappointing race in Sakhir, where both George and Valtteri lost the opportunity to win," said Toto.
"The pit stop problem has uncovered an underlying problem with our intercom, and we've put measures in place, both technically and in the way we operate, to make sure it doesn't happen again.
"There are still some question marks over who will be in the car this weekend in Abu Dhabi. Lewis's condition is improving, but we won't know until closer to the time if he will be driving.
"We'll do everything we can to get him in the car and we know he's determined to be back as soon as possible. But his health is our main priority, so we will see what the situation is and then make the call."