Elon Musk’s electric car company Tesla has issued their largest recall ever of their Model S vehicles due to a faulty steering issue.

The Verge reports that electric car manufacturer Tesla has recalled 123,000 Model S vehicles, stating that any of the vehicles built before April 2016 were affected by a power steering issue. Tesla previously recalled 90,000 Model S cars in 2015, and recalled 53,000 Model S and Model X cars in 2017 over a parking brake fault. This latest recall marks the largest recall Tesla has ever initiated.

Tesla said in an email to customers that the company had “observed excessive corrosion in the power steering bolts,” but that the problem mainly occurred in colder climates where road salt is commonly used. “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,” Tesla stated. “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.”

The company said that if owners had experienced no issues, their car was still safe to drive. For those that were affected, Tesla said that they would notify Model S owners when a retrofit, that would take an hour to install, would be available in their area. According to the Wall Street Journal, Tesla sold approximately 280,000 vehicles in 2017, with 123,000 now being recalled that accounts for approximately 43 percent of all cars sold by the company last year.

The Wall Street Journal recently reported that Elon Musk’s electric car manufacturing company Tesla may be in trouble as it continues to operate on a negative cash flow while production issues for their Model 3 vehicle mount. Moody’s Investors Service downgraded the company’s debt this week and generally has a negative outlook on the credit due to “the likelihood that Tesla will have to undertake a large, near-term capital raise in order to refund maturing obligations and avoid a liquidity shortfall.”