The Walkinshaw TWG driver was booted from the second race of the Sydney 500 weekend due to a technical breach relating to tyre pressure sensors.

Mostert’s Toyota Supra raced on two wheels that weren’t fitted with the sensors, prompting stewards to disqualify the reigning champion from the race and slap the team with a $5000 fine.

Here is the full statement from the stewards.

Fact
Two of the control wheels fitted to car 1 at the start of Race 2 were not fitted with operational TPMS sensors.

Rule
C2.1.1 – A car must comply with the GSD, relevant VSD, ESD and the rules.

Decision
Car 1 is disqualified from Race 2 and a fine of $5000 of which $2500 is suspended until 31 December 2026 on condition that a similar infringement is not committed by the team prior to that date.

Reasons
The CTM reported that no TPMS sensor reading was received from the two front control tyres fitted to car 1 at the start of the race. After the issue became apparent, the set of wheels and tyres removed from the car at its pit stop had been impounded at the direction of the stewards. The team said they were unaware of the issue before the race started. They speculated that the sensors had malfunctioned or had been damaged.

The TPMS sensors have two important functions, one being for Supercars Technical personnel to verify that the minimum tyre pressure of 16psi is met, the other being to provide data for the Ttam to provide feedback to the driver to optimise tyre temperature and thereby performance.

The team tendered their tyre set-up data for Race 2 which recorded that all four tyres fitted to car 1 at the start of the race were set to 16.6 psi (in excess of the minimum pressure).

They submitted that the non-operation of the TPMS sensors could be attributable to a range of factors outside the control of the team. They submitted that the stewards should not infer that the non-operation of the sensors was caused by a deliberate act by the team to avoid detection of under inflation of the tyres.

The stewards requested that the CTM check and record the pressures of the impounded tyres and to then deflate then and break the bead of the two control tyres concerned to check and remove the TPMS sensors. The hearing was adjourned to allow this to occur.

When the hearing resumed the CTM reported that there was no TPMS sensor fitted in either of the front wheels removed from car 1. The team acknowledged that the TPMS sensors were missing and attributed this to an oversight.

The pressures recorded in the impounded tyres did not suggest that they had been set at below 16 psi prior to the race (allowing for the change in ambient temperature from the start of the race and the time of the hearing).

The evidence does not suggest that the failure to ensure the TPMS sensors were fitted to the control wheels was deliberate or that any sporting advantage was gained. Nonetheless, it meant that the car did not comply with the rules because Rule D17.1.19 mandates that a control tyre must have an operational TPMS sensors fitted to the control wheel whenever it is fitted to the car. While there might be circumstances where a TPMS sensor is not operational due to no fault on the part of a team, in this case the sensors were not fitted at all. Whether a sporting advantage was or might have been gained from the non-compliance is irrelevant.

The Stewards therefore determine to disqualify car 1 from the classifications for Race 2 and impose a fine on the team.