Tesla has revealed that it installed older, slower processors in new cars because of supply chain issues caused by the coronavirus outbreak.The firm had received complaints from owners of new Model 3 vehicles in China who found their cars' computers used the older chip.In a statement, Tesla said it would upgrade the hardware free of charge, when supplies allowed.The chip in question is used by the car's Autopilot system.Autopilot provides semi-automatic driving, for example by taking control of steering, accelerating and braking.Owners of new Model 3 vehicles produced in China expected to find the 3.0 processor in their cars - but found the 2.5 version instead.The 3.0 chip has been included in new Tesla cars since April last year.It processes images 21 times faster than the 2.5 version.The first Tesla Model 3 vehicles made in China were delivered to customers on 7 January.However, due to the coronavirus outbreak, Tesla's factory in Shanghai closed at the end of January. It reopened on 10 February.