The incident came just 24 hours after the American crashed heavily on slicks on a drying track having made Q3 for the first time in his rookie season.
Sargeant stayed out on slicks in the wet early stages of the race and managed to survive the tricky conditions while losing a lot of time.
With the track dry he was running in last place when he speered off the road after touching the inside kerb at Turn 8 on lap 15.
In the immediate aftermath, he believed that something had gone wrong at the front of the car, telling the team: “I don’t know what happened, man. Something failed on the front right when I hit the kerb.”
Vowles confirmed that the crash was sparked by a hydraulic issue that affected the steering.
"On review of everything, it's very early days, but what I can explain is this,” he told Autosport. “There's an apex kerb, he ran over the kerb multiple times.
“It wasn't the first time of the race, we can find at least three or four laps before then he was there as well. He also ran over it on Friday.
“And this particular point there's quite a large spike of load through the floor, and that ends up in a situation where as soon as he hits it, we lose all hydraulic pressure.
“When you lose hydraulic pressure in an F1 car, you have no steering and no other things. So he wouldn't have known that in the milliseconds that happened.
“But it's not the same circumstances as before [in qualifying]. We need to understand that from our perspective."
Sargeant admitted he was mindful of the qualifying incident while running on slicks in the wet early stages of the race.
"It was a tricky first 15 laps just being too cautious, not wanting to crash after what happened yesterday,” he said.
“I was just losing a bit too much tyre temp in those wet conditions, which cost me a lot of time. But apart from that I was starting to get back into a rhythm as the track was drying.
"I touched the apex kerb at Turn 8 and I lost hydraulics and power steering. And that just set me off. And once I touched all the damp stuff, there was really no chance of recovery.
“Not sure why exactly that happened. Something we need to look into, for sure. But honestly, just disappointed for everyone who put in the effort to have it ready for today, disappointing for the team, another destroyed car."
Regarding the kerb strike, he added: “I've used it all weekend, to be honest. And it wasn't like I was hitting it crazy hard. But I was definitely using it throughout the weekend. It was always okay, so I’m not sure.”
Sargeant admitted that he would have preferred to have been given the option of going to intermediates in the wet early stages.
"I think maybe because of what happened yesterday [Saturday] it would have been nice to come in and put inters to have that confidence to push,” he said. “But at the end of the day, the end result was unfortunately inevitable."
Vowles conceded that it might have been a better choice for the youngster: "Easy in hindsight, but what we're concerned about is by lap three at the point you've got to commit one way or the other, and we'd committed,” he said.
“But I think definitely if you go back on it and go should we have put him on inters in those difficult conditions? Yes.
“As I said something else has gone wrong [in the crash], and we've got to understand that. But it would have helped his confidence."
