The question isn't terribly clear. IF there is no VAT to pay (which appears to be presumed in the question) then it's exempt, not zero rated.
If it's a company now selling a car they've previously been using as a company car for one of their staff then it does, as someone said above, depend on how the car was treated whilst with them whether there should be VAT involved. If it was only used for business mileage (didn't go to anyone's home at night) then it's a qualifying car, VAT should have been claimed on it when it was bought and should be charged on it when sold. If it had private mileage at all then it should have had no vat claimed on it to date and none charged now unless it's actually being sold for more than it cost, in which case you have to pay VAT on the margin.
If it's a garage selling a car to a company then it would be normal VAT charged.