Tombazis links Sepang formation-lap failures to a software bug
GPBeat reports that Nikolas Tombazis linked Sepang’s formation-lap power problems to a software bug triggered amid very slow, near-stationary running. He estimated the software response at about 20 minutes; the race restarted after a 53-minute red-flag delay.
Rain had already delayed the start at Sepang by 40 minutes when several cars suffered power problems on the formation lap, prompting a red flag before the Bahrain Grand Prix in Malaysia could begin.
FIA official Nikolas Tombazis said a combination of very slow cars and a concertina effect, with some cars nearly at a standstill, triggered the bug. It prevented power from being redeployed, leaving affected cars unable to get moving again.
At the post-race FIA press conference, Hamilton said his power did not return during the pre-start problem and he had to stop on track and restart the car.
Tombazis said FIA staff quickly identified the problem and issued a software update for teams to install. He estimated that response at about 20 minutes. The race restarted after a 53-minute red-flag delay.
Verstappen separately described the actual race start after the stoppage: he said he had no power as he dropped the clutch and the engine died.
Tombazis said the software had not been tested as extensively as he would have liked because there had been very little wet running that season. He said more testing probably would have caught the bug in time.
Sources 02
- SOURCEFIA explains software glitch that caused Bahrain GP in Malaysia race delayAutosport
- PRIMARY SOURCEF1 - 2026 Bahrain Grand Prix in Malaysia Post-Race Press Conference TranscriptFIA news and transcripts
Claims and supporting evidence 8
Autosport reports the weather delay and the formation-lap problems leading to the red flag.
Autosport quotes Tombazis explaining both the circumstances that triggered the bug and its effect.
The FIA post-race press conference transcript records Hamilton’s account.
Autosport quotes Tombazis on the update process and its estimated duration.
Autosport gives the delay before the restart.
The FIA transcript records Verstappen’s account of the race start; the article keeps it distinct from the formation-lap problem.
Autosport quotes Tombazis on the testing limitation.
This preserves Tombazis’s qualified view of what additional testing might have achieved.
Corrections and updates to this story
FIA director links Sepang pre-start stoppage to low-speed software bug
Updated to add that Mercedes-powered cars initially appeared less affected, with Tombazis saying differing mini-sector speeds—not a technical reason—accounted for the pattern; to clarify that the emergency change was not a watertight solution for future races; and to report that his guarantee applied only to this specific fault. The MGU-K explanation remains an attributed initial suggestion; its technical definition has been removed. / Bijgewerkt met de aanvankelijke indruk dat auto's met een Mercedes-motor minder getroffen leken, en Tombazis' uitleg dat uiteenlopende snelheden in mini-sectoren daarvoor de verklaring waren, niet een technische reden; verduidelijkt dat de noodmaatregel geen sluitende oplossing voor toekomstige races was; en vermeld dat zijn garantie alleen voor deze specifieke fout gold. De MGU-K-verklaring blijft een toegeschreven eerste suggestie; de technische omschrijving is verwijderd.
Tombazis links Sepang formation-lap failures to a software bug
Updated to add Tombazis’s explanation that very slow cars and a concertina effect on the formation lap triggered the bug, his account of the limited wet-weather testing, Hamilton’s account of the pre-start power failure and Verstappen’s separate account of the race-start power loss. The update distinguishes Tombazis’s estimate of about 20 minutes for the software response from the 53-minute delay before the restart. An earlier update noted that Mercedes-powered cars initially appeared less affected; Tombazis attributed the pattern to differing speeds in mini-sectors, not to a technical difference. That update reported Motorsport.com’s characterization of the emergency change as not a watertight solution for future races and noted that Tombazis’s guarantee applied only to this specific fault. The earlier version described the possible MGU-K explanation as an initial suggestion. / Bijgewerkt met Tombazis’ uitleg dat zeer langzaam rijdende auto’s en een harmonica-effect tijdens de formatieronde de fout activeerden, zijn toelichting over de beperkte tests in natte omstandigheden, Hamiltons beschrijving van het vermogensprobleem vóór de start en Verstappens afzonderlijke beschrijving van vermogensverlies bij de race-start. De update maakt onderscheid tussen Tombazis’ schatting van ongeveer 20 minuten voor de software-ingreep en de vertraging van 53 minuten tot de herstart. Een eerdere update vermeldde dat auto’s met een Mercedes-motor aanvankelijk minder getroffen leken; Tombazis schreef dat toe aan uiteenlopende snelheden in mini-sectoren, niet aan een technisch verschil. Die update schreef aan Motorsport.com de typering toe dat de noodmaatregel geen sluitende oplossing voor toekomstige races was en vermeldde dat Tombazis’ garantie alleen voor deze specifieke fout gold. De eerdere versie beschreef de mogelijke MGU-K-verklaring als een eerste suggestie.
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