Honda has admitted that recurring battery problems are continuing to undermine Aston Martin’s Formula 1 campaign, with the manufacturer’s reliability improving in the middle of the 2026 season before deteriorating sharply across the latest three race weekends.
The scale of the problem became increasingly apparent during the United States, Mexico City and São Paulo Grands Prix, where five of Aston Martin’s six race starts ended in retirement. Fernando Alonso was the only driver to reach the chequered flag across that sequence, finishing 12th in Brazil.
The latest setback came at Interlagos, where Lance Stroll retired after encountering a battery-related problem. Honda has acknowledged that although it understands what happened to the Canadian’s car, it has yet to establish the underlying cause of the recurring failures.
For a partnership that needs to demonstrate substantial progress ahead of 2027, the admission raises further questions about Honda’s ability to deliver the reliability and performance Aston Martin requires.
Honda admits power unit weaknesses were hidden by Brazilian rain
Aston Martin arrived in Brazil with some encouragement after Alonso secured eighth on the grid, the team’s strongest qualifying position of the season.
The Spaniard initially looked competitive in the changing conditions, battling with Lewis Hamilton and Alexander Albon before eventually slipping to 12th as the track dried.
Alonso subsequently acknowledged that the car had shown reasonable performance through the corners but continued to struggle on the straights.
Honda’s Shintaro Orihara explained in an interview with Spanish newspaper AS that the wet conditions had disguised some of the power unit’s underlying weaknesses.
“In wet conditions, our weaknesses regarding engine performance and energy deployment are hidden. However, drivability becomes more important, and that’s another area we still need to improve. There’s room for improvement for the next race, and especially for next year.”
His comments highlight the two separate challenges confronting Honda: extracting more performance from its power unit and improving the way electrical energy is recovered and deployed.
The 2026 regulations have significantly increased the importance of electrical energy within the power unit, placing additional emphasis on energy management and deployment.
In Brazil, the reduced speeds and changing grip levels helped disguise some of Aston Martin’s limitations. However, the underlying performance deficit became more apparent as conditions improved.
Five retirements from six starts expose Honda reliability concerns
Performance is only part of Aston Martin’s problem.
The team’s reliability has become increasingly concerning, particularly given that Honda had appeared to make progress during the middle portion of the season.
Across the triple-header in the United States, Mexico and Brazil, Aston Martin recorded five retirements from six possible race starts.
Stroll’s latest retirement came on lap 30 at Interlagos. He lost speed on the exit of Turn 12 before returning towards the pits, but the car could not make it back to the garage.
The problem was particularly frustrating because Stroll had also experienced ERS-related difficulties during qualifying, raising the possibility that the two incidents were connected.
Orihara acknowledged that the situation had deteriorated after a period of improved reliability.
“Our reliability was much better in the middle of the season. In the last three races, we’ve been experiencing similar problems that are unrelated to mileage or component load, particularly with the battery.”
He added:
“We understand what kind of problem Stroll’s car had, but we don’t know the root cause yet. We need to understand that first.”
That admission is significant. If the problems were simply the consequence of component wear or excessive mileage, Honda could potentially address them through more straightforward changes to its operating procedures or replacement schedules.
Instead, the manufacturer is facing recurring failures that it has yet to fully explain.
Honda’s official post-race assessment also indicated that the ERS problem affecting Stroll in Brazil could have been related to the issue experienced during qualifying.
Identifying the underlying cause before the next race in Las Vegas has therefore become an important priority.
Mike Krack acknowledges Aston Martin’s growing frustration
Aston Martin chief trackside officer Mike Krack also acknowledged the scale of the team’s reliability difficulties, despite seeing encouraging signs in its competitiveness at Interlagos.
“The conditions were difficult, but our competitiveness had improved a bit, especially in the final. Considering the situation this season, I think it was a good performance.”
“Unfortunately, we didn’t score any points. That’s the result we’ll take away from this weekend. However, we were able to run ahead of our faster rivals.”
Krack was particularly direct when discussing the reliability record across the previous three events.
“Nevertheless, in the last three races, five out of six opportunities to start ended in retirement. This is an issue we need to address. We were positive in terms of competitiveness, but not in terms of reliability.”
The comments underline the contradiction currently facing Aston Martin. The team has occasionally demonstrated enough pace to challenge more established competitors, but mechanical failures continue to prevent that progress from translating into meaningful results.
Honda president visits Brazil as 2027 preparations intensify
Honda president Toshihiro Mibe was also present at the São Paulo Grand Prix, where he met Aston Martin owner Lawrence Stroll and other senior team representatives.
The visit comes at an important point in the manufacturer’s relationship with Aston Martin.
The two companies began their works partnership in 2026, but the first season has proved considerably more difficult than either side would have wanted.
With only three races remaining in the 2026 campaign, Honda must now establish why its battery-related problems have returned while continuing to address the power unit’s performance, energy deployment and drivability.
The Brazilian weekend offered some evidence that Aston Martin can be more competitive in the right conditions. However, without a dependable power unit, those improvements risk remaining little more than isolated glimpses of potential.
For Honda, the immediate priority is to identify the root cause of the recurring failures before the Las Vegas Grand Prix. Longer term, the manufacturer needs to demonstrate that the lessons of a difficult first season can be translated into a far more competitive and reliable package for 2027.
Aston Martin needs more than occasional flashes of speed. It needs a Honda power unit capable of finishing races.
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The Judge, a nom de plume of an experienced F1 journalist and site founder with long-standing sources across the paddock. With over 30 years of experience in Formula 1 as an insider journalist, I have built trusted connections across the paddock, from race engineers and mechanics to senior team figures. At The Judge 13, I and a handful of trusted colleagues share exclusive Formula 1 news, expert analysis and behind-the-scenes stories you will not find in mainstream motorsport media.
Thiago Treze is a Brazilian motorsport writer at TJ13 with a background in sports journalism and broadcast media, alongside an academic foundation in engineering with a focus on Computational Fluid Dynamics (CFD). This combination of technical knowledge and editorial experience allows Thiago to approach Formula 1 from both a performance and narrative perspective.
At TJ13, Treze covers driver performance, career developments, and key storylines across the Formula 1 grid, while also analysing the technical factors that influence competitiveness. This includes aerodynamic development trends, simulation-driven design approaches, and the engineering decisions that shape race weekend outcomes.
His reporting bridges the gap between human performance and machine development, helping readers understand how driver execution and technical innovation interact in modern Formula 1. Coverage often connects on-track events with the underlying engineering philosophies that define each team’s approach.
With a global perspective shaped by both journalism and technical study, Thiago also focuses on Formula 1’s international reach and the different ways the sport is experienced across regions.
Treze has a particular interest in how Computational Fluid Dynamics and aerodynamic modelling contribute to car performance, offering accessible explanations of complex technical concepts within Formula 1.
