It looks like Tesla Motors' brief firefight is now over.

Not only has the company announced the fitment of new parts designed to deflect road debris, the cause of two fire incidents towards the end of 2013, but the NHTSA has now closed its probe into the fires--absolving the Model S of blame.

Last year, Tesla had to defend its cars following three separate fire incidents in quick succession.

In the first two incidents, drivers had hit debris in the road at highway speeds, which punctured the battery pack of each car which subsequently caught fire.

A third incident involved a high-speed accident in Mexico, in which a Model S was driven through a wall at speed. That car too caught fire following the accident.

ALSO SEE: Tesla Model S To Get Titanium Battery Shield, Plus Deflectors: BREAKING

No drivers or passengers were harmed in the incidents--indeed, all credited the Model S's incredibly strong body with saving their lives. In the two road debris incidents, the drivers were able to pull to the side of the road and get out before the fire started.

While the NHTSA's statement notes that both cars affected in the debris incidents were operating with the active suspension in its low, aerodynamic position at highway speeds, the safety body has not identified any defect with the vehicles.

It also notes that Tesla's immediate action to raise the ride height of vehicles traveling at highway speeds "should reduce both the frequency of underbody strikes and the resultant fire risk". As the car's safety has been improved and no defect was found, the investigation is closed.

In addition to Tesla's ride height modifications--a simple software update--the company announced yesterday it would fit every new Model S and every car already in the hands of customers with an additional titanium and aluminum protection plate.

Comprising three sections for both protection and object deflection, Tesla has trialed the new protection plate in 150 tests. No battery pack damage occurred during the tests, nor any fire incidents.


Follow GreenCarReports on FacebookTwitter and Google+