Tesla has issued a voluntarily recall for roughly 53,000 of its Model S and Model X electric cars to address an issue in which the parking brake might stick in the engaged position.

The recall was first reported yesterday by CNBC. The vehicles affected were built between February and October of 2016, and 31,000 of them were sold in the U.S.

It is Tesla's first vehicle recall in a year; the company replaced third-row seat backs in 2,700 of the earliest Model X electric crossover utilities. That recall was announced a year ago.

DON'T MISS: Tesla Model X recall replaces third-row seat backs (Apr 2016)

Tesla calls yesterday's action a "voluntary recall," and stresses that only a small number of the 53,000 vehicles—less than 5 percent, perhaps as low as 2 percent—is likely to suffer from the problem.

A letter to Tesla owners, obtained and published by TechCrunch, stresses that the company does not know of a single accident or injury that has resulted from the issue.

The specific problem involved an internal gear in the parking-brake assembly, supplied by Brembo, that could fracture once engaged, leading the brake to remain "on."

2016 Tesla Model X

2016 Tesla Model X

While only a small number of cars will have the defective gears, Tesla will replace them all because it's difficult to tell by looking at them whether they're bad.

Tesla will file the recall with the NHTSA, and the Silicon Valley carmaker says it expects to have received all necessary repair parts by October.

Replacing both parts on the car's parking-brake assembly takes less than an hour.

The recall process is starting now, and Tesla says it expects it to be completed by October if all 53,000 vehicles are returned for inspection.

In its letter to owners, Tesla wrote:

We have determined that the electric parking brakes installed on Model S and Model X vehicles built between February and October 2016 may contain a small gear that could have been manufactured improperly by our third‑party supplier.

2016 Tesla Model S

2016 Tesla Model S

If this gear were to break, the parking brake would continue to keep the car from moving, but the parking brake would then be stuck in place.

There have been no reports of the parking brake system failing to hold a parked vehicle or failing to stop a vehicle in an emergency as a result of this condition, and this part has no impact on the car’s regular braking systems.

We have also determined that only a very small percentage of gears in vehicles built during this period were manufactured improperly.

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While the repair is expected to take less than an hour, it affects roughly one quarter of all the cars built by the company in its history.

What effect that may have on waiting times for service calls remains to be determined.

Tesla owners continue to complain in online forums and other venues of long waits and overloaded service sites as the company's sales continue to rise.

Map of Tesla service center locations in the U.S., December 2016

Map of Tesla service center locations in the U.S., December 2016

Previous Tesla recalls include the replacement of about 7,000 electric-car charging adapters after two reports of overheating resulting in melted plastic on the adapters. That recall, which did not result in any injuries or property damage, was reported by Bloomberg in December 2016.

Earlier, Tesla issued a voluntary recall for 1,228 Model S electric sedans manufactured between May 10 and June 8 of 2013 to fix a potentially weakened left-rear seat attachment striker bracket.

To see full details on the current recall, Tesla owners can visit the company's Recall Information page. For further assistance, they can also call Tesla at 877-798-3752 or e-mail it at: ServiceHelpNA (at) tesla (dot) com.


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