> ## Content Index > Fetch the complete content index at: https://slipstreampaddock.com/llms.txt > Use this file to discover other available public pages before exploring further. # Software meets wet asphalt at Sepang: how the 2026 power units lost power - URL: https://slipstreampaddock.com/sepang-formation-lap-software-chaos-2026/ - Published: 2026-10-04T16:03:48.000Z - Updated: 2026-10-04T16:51:09.000Z - Description: F1's Bahrain Grand Prix at Sepang started 90 minutes late after rain triggered software power loss on formation lap. Analysis of the 2026 power unit deployment issue. - Author: Kris Pinter - Tags: News, Analysis, F1, 2026 Regulations The Bahrain Grand Prix in Malaysia, run at Sepang International Circuit on 4 October 2026, started over 90 minutes late after rain triggered a software-related power loss on the formation lap. Several cars stopped on track behind the safety car, the start was abandoned, and an emergency software update was distributed to all teams before the race finally began. The issue was not mechanical failure. It was an interaction between low engine speeds, wet-weather energy management settings, and the 2026 power unit's deployment maps. ## Formation lap sequence The start was delayed 40 minutes for heavy rain. When the cars formed up behind the safety car, drivers reported no power response. Max Verstappen described the car at 35 km/h (22 mph) and still losing speed on an uphill section. Lewis Hamilton told Ferrari over radio: "I'm pressing the throttle and nothing's happening." He stopped on track to restart systems. Isack Hadjar lost grip behind the safety car and later said the car felt like it had "no battery" in the final laps. Lando Norris called the scenes "horrible" and said it proved "we shouldn't have any of that stuff, the electronic side." Multiple cars stopped. The safety car eventually lapped some of the field. Teams pushed cars into correct grid order in the pit lane. The FIA issued a red flag. The start was suspended for about 53 minutes while teams installed a software update. ## FIA statement The governing body's statement: > "On the formation lap ahead of the Bahrain Grand Prix in Malaysia, an unprecedented combination of low engine speed, low-grip conditions, wet-weather energy management settings and the Sepang circuit's sector configuration led to an unintended loss of power for a number of cars." The FIA Technical Department removed the energy limit constraint in affected sectors through an updated software release distributed to all competitors during the delay. The statement added: "This issue had not been detected by the FIA or the teams during testing or during the laps to the grid. The FIA, together with the teams and Power Unit manufacturers, will undertake a full review of the issue." FIA single-seater director Nikolas Tombazis said F1 had never had competitive running in wet conditions this season. He said the formation lap saw cars go "very slowly, almost came to a standstill" with a concertina effect, and the bug prevented power redeployment. ## Technical explanation: deployment maps The 2026 power units use a near 50-50 split between internal combustion engine and electric motor. Electric deployment is mapped to track position, not directly to throttle input. When cars crawled at low speeds behind the safety car in wet conditions, the software became confused about track position. Deployment maps release energy based on where the car is on circuit. Low grip meant drivers used less throttle than normal. Low engine speed meant less electrical generation. The combination created a deficit. The FIA's explanation: cars could not redeploy stored electrical energy because the software was waiting for conditions that never arrived. Some cars effectively ran on the ICE alone, which at 35 km/h and uphill could not maintain speed. The problem was exacerbated by Sepang's sector configuration and the specific energy management settings used for wet weather. ## Driver reactions Verstappen: "I hope there is a lesson learned." He joked the delay became "because they had to update the software, and then you have to load it into the car. I guess some had some faster laptops than others." Hamilton compared the cars to Lego: "It was like the Lego race. Same speed." Norris: "Horrible." He added the episode showed "we shouldn't have any of that stuff, the electronic side." Hadjar: "No pace. Something was wrong, because… I can't possibly be a second a lap slower now." He said the car was "horrible to drive" and "it's a joke." ## Analysis: testing gap The FIA had not tested the 2026 software extensively in wet conditions. The sport had seen no rain in 2026 before Sepang. The combination of factors was unique: very low speeds, low grip, wet-weather energy maps, and Sepang's specific sector layout. This is not a hardware failure. It is a software edge case that emerged from real-world conditions the simulations had not covered. The fix was removing energy constraints. The review will need to address whether deployment maps can be made more robust to speed variations and whether the system should default to driver demand in low-speed situations. ## Race outcome after restart The race started with a much drier track. The software update removed the energy limit constraint. Verstappen won from pole. Kimi Antonelli finished second, Hamilton third. The event took over three hours from scheduled start to chequered flag. Championship lead: Antonelli leads Russell by 84 points after Russell retired with engine failure late in the race.