Le Mans 2019 results: Toyota reveal what happened to cost the No 7 victory and hand win to No 8 car

A faulty sensor sent false data to the team and caused them to remove the wrong wheel, sending Jose Maria Lopez back out on the track with a deflated tyre that cost them certain victory

Toyota have revealed how a faulty sensor was behind the controversial error that cost the No 7 TS050 of Mike Conway, Kamui Kobayashi and Jose Maria Lopez victory in the Le Mans 24 Hours, with the team mistakenly replacing the wrong wheel as a result.

Having led the most famous race in the world for nearly 12 hours consecutively, Lopez looked to have avoided a potential setback when the team identified a deflating tyre, with the Argentine able to make it to the pits without losing much time to the sister No 8 car of Sebastien Buemi, Fernando Alonso and Kazuki Nakajima.

In an attempt to reduce the time in the pits with just one hour remaining, Toyota elected to change just the punctured tyre, swapping the right-front and sending Lopez on his way as he retained the lead.

But disaster immediately struck when Lopez reported another puncture on his out-lap, with the No 7 car limping round the 8.3-mile circuit and losing the lead to Nakajima, who went on to take victory and seal a second successive win for the No 8 car despite trailing in second for the bulk of the race.

Addressing the controversial events after the race, Toyota’s LMP1 team boss Rob Leupen revealed that false data from the car hid the fact that it was the right-rear tyre, not the front one, that was punctured, causing the team to send Lopez back out with the deflated tyre still attached after removing a fully-working Michelin. But questions were immediately asked over why the team did not change all four tyres as they would normally do when suffering a puncture, given they had the lead to do so.

"The simple question was asked why we didn’t change all four tyres to be safe," Leupen said. "We didn’t do that. It’s all in the game and then you have to make a decision.

"I don’t know what happened (with the sensor). I don’t think we’re really thinking about that right now. I think the people of the No 7 car have a lot of problems with this and we first have to accept it."

Conway, Kobayashi and Lopez appeared disconsolate after the race, though they were invited to lift the race-winning trophy alongside the triumphant trio as Alonso admitted “the No 7 deserved to win today”, and Leupen was torn on his emotions with the success of a one-two result balanced out by heatbreak for the dominant team - who for Conway and Kobayashi finished runner up for the third time in four years.

“It’s very difficult. We wanted to make it really boring, but that didn’t happen. The No 7 car was by far the fastest of the two, they all worked very hard.

"We got into a situation where we caught a puncture at the end, and it hurts a lot that the team didn’t respond well to that.”

Toyota sent the No 7 car out of the pits with a puncture due to a faulty wheel sensor (Getty)

The minutes after the puncture controversy saw a number of mixed messages sent over the radios of both Toyotas, with Lopez warned against wrecking the car in his valiant attempt to chase Nakajima down and the Japanese given no answer when he asked if he needed to push on his final in-lap, before being told to not go any faster to avoid having to complete another lap.

Leupen revealed that in those confusing minutes, the team discussed swapping the two cars around to give the No 7 team the win they deserved, with the fact that none of Conway, Kobayashi or Lopez have won the prestigious endurance race.

Alonso, Buemi and Nakajima inherited victory after the error (AFP/Getty) (AFP/Getty Images)

But in the end the decision was to let the race play out, giving Alonso his triumphant Toyota farewell and allowing the No 8 to take race victory along with the World Endurance Championship LMP title, with a Japanese driver taking the chequered flag in a Japanese car the dream scenario for the Toyota board.

"We thought about doing something, but that wouldn’t have been correct,” Leupen added.

"We talked it through with the drivers and I think we did the right thing. Le Mans chooses its winner again.”