Explained: The “serious” car problem that led to Racing Bulls’ penalty at F1 Canadian GP

Racing Bulls has been handed a part-suspended fine after a “serious” problem was discovered on Liam Lawson’s Formula 1 car following his stoppage in Canadian Grand Prix practice.

Lawson ground to a halt just 10 minutes into the sole practice session at the Circuit Gilles Villeneuve on Friday, with his stoppage resulting in the first of three red flags.

It has now emerged that the red flag had to be deployed because marshals were unable to move Lawson’s stricken Racing Bulls car due to a fault with the Clutch Disengagement System (CDS).

The CDS is a button on the exterior of an F1 car which marshals use to disengage the car’s clutch and allow the wheels to turn in the event of a recovery.

Racing Bulls had already been warned about its CDS last year by the stewards, who described its failure as a “serious” matter.

The Faenza-based outfit was subsequently handed a €30,000 (£25,900) fine, two-thirds of which is suspended for 12 months subject to no further breach of this regulation by the team.

“The team’s engineer explained how the CDS system worked,” the stewards reported.

“It was noted that the system on this car performs two roles – the one for which is it primarily intended, namely to release the clutch when the car is stopped and the engine is not working, and the other relates to the anti-stall system.

“In this case, a ruptured joint caused a hydraulic leak, which caused the car to stop. The CDS, when activated by the marshal, then failed to release the clutch and hence the car could not be moved.

“This is a serious matter. It resulted in the session being red-flagged. Had the system worked as intended by the regulations, the incident could have been dealt with swiftly via deployment of the Virtual Safety Car.

“The Stewards note the concern of the FIA Technical Delegate, over the dual purpose of the CDS on this car. The Technical Delegate advised that the team had, in 2025, been warned about the CDS system design for its cars.

“The driver noted that there were two issues of concern that he wished to draw to the attention of the stewards, namely that contrary to his instructions and common practice, the marshals attempted to push the car when it was stationary, and that the marshal who attempted to activate the CDS was trying to press a button on the on-board camera rather than the CDS button.

“This indicates to the stewards that further training in this area is required, notwithstanding the fact that the FIA distributes a very clear document addressing this action. (ref “FIA Single Seater Recovery Specifications”).

“We note that it is obvious that the distribution of such a document, although well detailed, probably needs supplementing with some form of practical training by the organisers.”

The F1 regulations state that the CDS system “must be in working order throughout the Competition even if the main hydraulic, pneumatic or electrical systems on the car have failed”. 

Lawson was unable to take part in sprint qualifying as a result of the failure on his car.