Haas was hit by electronics problems which brought its encouraging first test to an early end on Thursday.
Esteban Gutierrez completed a race simulation during another impressive day of running for the new team before he stopped on track with a little over an hour of the session remaining. The Mexican did not run again on the final day and team principal Guenther Steiner explained the cause of the stoppage.
"Some electronics problems," Steiner said. "It happens, thankfully it was only with an hour to go so it wasn’t too bad. We were planning to go out on softer tyres but you cannot win them all!
"This morning we had the brake problem, overheating. We were still finding how much how to blank off to find our threshold cooling system because we were never out for this many laps. We found that one out and in the afternoon it was solved because we stayed out for a long run, almost a complete race distance, which was pretty good."
And Steiner declared himself pleased with the lack of major problems Haas faced despite learning about many new parts which it has not manufactured itself.
"We just overheated once the brake and we had the front wing problem but otherwise we didn’t have a lot of problems. With these cars when you get the small problem it takes a long time to fix, they are so complicated, that is the problem.
"The brake problem, to change the disc and to bleed the whole thing takes two hours and you’ve got eight hours of running time, so it seems a lot. So a small mistake - it’s not even a mistake, it’s a small learning experience - can end up in being two hours down.
"The mechanics are still learning the car. We are four days old so we are learning while we do it. I don’t think that we have a lot of problems, we have got small problems but they take a long time to sort out."
REPORT: Raikkonen fastest as McLaren completes just three laps
Day four of the first test as it happened
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