The US National Highway Traffic Safety Administration (NHTSA) has opened an investigation into around 115,000 Tesla cars after a number of incidents involving suspected failure of the front suspension.
In a statement, the NHTSA said the failure concerns the Tesla Model S built from 2015-2017 and the Tesla Model X SUV that were produced from 2016-2017.
According to the US safety body, it has received 43 complaints alleging that the left or right suspension control arms have failed – a fault that could be potentially lethal.
The NHTSA said Tesla was aware of the issue, as the car-maker issued a service bulletin back in February 2017 describing a 'manufacturing condition' that may cause the failures.
Despite this, no recall has been conducted.
In the bulletin, Tesla admitted the suspension components "may not meet Tesla strength specifications", but insisted that if they fail the driver can "still maintain control of the vehicle but the tyre may contact the wheel-arch liner".
The NHTSA said 32 of the complaints reported to it occurred during low-speed parking manoeuvres and 11 while driving, with a further eight unspecified failures.
It's not clear if any resulted in an accident or even injuries but, alarmingly, the NHTSA reports that the complaints indicate an "increasing trend" with three of the incidents occurring at highway speeds recorded in the past three months.
This suggests that as the Tesla Model S and Model X age, the more prone they could be to suffering a failure.
As well as the NHTSA investigation, earlier this month a class action lawsuit was filed against Tesla in California over suspension issues concerning not only the front suspension control arms failing but the rear ones too.
Fuelling frustrations with owners and the NHTSA, the US car-maker said in October that it was recalling 30,000 Model S and Model X vehicle in China at the request of Chinese regulators, but had no plans to do the same in the US "because the environment in China required stronger suspension due to local roads and driving conditions".
A second Tesla recall for the Chinese market has also been issued concerning the rear suspension links.
Responding to the NHTSA, Tesla said it did not believe there was any suspension defect, claiming any issue in the US was "exceedingly rare".
It also said it was unaware of any related crashes, injuries or deaths worldwide.
As well as the failing front suspension, the US safety body has another separate probe into nearly 159,000 Tesla Model S and Model X vehicles that involves touch-screen failures that result in the loss of the rear camera image while in reverse.
Another issue concerns the cameras' defogging ability and audible chimes that should emit when operating the indicators or Autopilot cruise control.
The second investigation covers 2012 Tesla Model S and 2016-2018 Model X vehicles.
It's not known if, or how many, Tesla Model S or Model X vehicles might be affected with either issue in Australia.