a code reader is a device that plugs into your cars systems to tell you what faults have been detected,this is done by a garage with the right equipment, you might have to look on gearbox for filler level, as for price, that will depend on work done, i have a vw sharan and to have a new g/box seal, new filler pipe, and 5lts of fluid was charged £175-00 inc vat. but £110-00 was labour charges.(took just over an hour to do) i normally do this work myself, but due to previous owner using a "cowboy" fu&ked up the g/box hence using an auto trans techie. so be prepared for paying out if you have major problem, but hopefully just need a top up of fluid. Good Luck.
hope it helps, September 2010
