McLaren spent Friday night in Monaco working well past the paddock curfew to fix the electrical fault that stopped Lando Norris on track during the second practice session — using one of the four curfew exemptions each team is permitted across a season.
Norris’s car shut down mid-session in FP2 at Circuit de Monaco, costing the reigning world champion valuable laps on a street circuit where every metre of muscle memory matters. The team chose to act comprehensively rather than patch the problem overnight.
“Following Lando’s car stopping on track in FP2 yesterday, the team carried out extensive work ahead of FP3 this morning,” McLaren said on Saturday. “To investigate and address the issue comprehensively, the team elected to break curfew last night and replace the wiring harness, and also changed the ESME pack within the permitted allocation.”
What they replaced — and why it matters
The wiring harness is essentially the car’s central nervous system, routing electrical signals and power to dozens of components. The ESME — Energy Store Main Enclosure — is an external structure that houses multiple safety sensors, elements, and associated wiring for the hybrid power unit. Under 2026’s heavily electrified power unit regulations, where roughly half of total power output comes from the electrical side of the drivetrain, the ESME’s reliability is even more critical than in previous generations of car.
Crucially, McLaren confirmed that both components were swapped within Norris’s existing allocation, meaning no grid penalty should follow. The team’s swift action appears designed to ensure Norris headed into FP3 — the final 60-minute session before qualifying on a track with zero room for mechanical surprises — with full confidence in the car.
Cadillac also broke curfew — a small piece of history
McLaren were not alone in burning a late-night exemption. Cadillac also broke curfew on Friday at Monaco, marking the first time the American outfit has done so since joining the grid as F1’s eleventh team at the start of 2026. It is a small but telling milestone: curfew breaks are typically reserved for significant mechanical concerns, and the fact that Cadillac needed one in only their debut season reflects both the complexity of racing at Monaco and the learning curve facing any new constructor.
Teams are allowed exactly four curfew exemptions per season under the sporting regulations. With Monaco typically falling relatively early in the calendar, burning one here is not catastrophic — but every exemption used is one fewer available for the pressure-cooker weekends later in the year.
What’s at stake for Norris
Monaco has historically been one of the most difficult circuits for a title leader to manage risk. Any mechanical uncertainty compounds that pressure. With Norris defending his championship in 2026 under the sport’s radical new technical regulations — new chassis architecture, new power units, active aerodynamics — reliability has been an industry-wide talking point all season. A clean run through qualifying and the race would do more than just deliver points; it would signal McLaren have their electrical gremlins fully under control.
Qualifying at Monaco is effectively the race result written in advance. If the wiring harness replacement holds and Norris can find his rhythm on the street circuit, Sunday’s outcome could be decisive in the early championship picture. The Monaco Grand Prix starts Sunday, 8 June.