Tesla is voluntarily recalling 123,000 Model S vehicles because of an issue with the power steering component.

This problem is limited to Model S cars built before April 2016. Tesla said Model X and Model 3 cars are not included in this recall.

Shares of Tesla fell nearly 4 percent in after-hours trade on Thursday.

In an email to customers, the electric automaker explained that it has seen "excessive corrosion" in the power steering bolts of the affected vehicles. Tesla said that if the bolts fail, the driver would still be able to steer the car, but would have to use "increased force."

"This primarily makes the car harder to drive at low speeds and for parallel parking, but does not materially affect control at high speed, where only small steering wheel force is needed," Tesla wrote in its email to customers.

Tesla said it has only seen this problem occur in "very cold climates" where road salts are commonly used. But the company said it was recalling all affected vehicles regardless of climate, "to account for the possibility that the vehicle may later be used in a highly corrosive environment."

Here is the email Tesla sent to its customers.

In order to ensure your safety, Tesla will proactively retrofit a power steering component in all Model S vehicles built before April 2016. (No other Tesla vehicles are affected.) There have been no injuries or accidents due to this component, despite accumulating more than a billion miles of driving.



To be clear, this recall does not apply to any Model X or Model 3 vehicles, only to Model S vehicles built before April 2016.



We have observed excessive corrosion in the power steering bolts, though only in very cold climates, particularly those that frequently use calcium or magnesium road salts, rather than sodium chloride (table salt). Nonetheless, Tesla plans to replace all early Model S power steering bolts in all climates worldwide to account for the possibility that the vehicle may later be used in a highly corrosive environment.



If the bolts fail, the driver is still able to steer the car, but increased force is required due to loss or reduction of power assist. This primarily makes the car harder to drive at low speeds and for parallel parking, but does not materially affect control at high speed, where only small steering wheel force is needed.



Our records show that you own a Model S affected by this voluntary recall. At this time there is no immediate action you need to take and you may continue to drive your Model S. Tesla will contact you to schedule an appointment when parts are available in your region. The retrofit will typically take around an hour.



Thank you for being a Tesla customer, and we apologize for this inconvenience. If you have any questions, please contact us by phone at 844-248-3752 or by email at ServiceHelpNA@tesla.com.

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