Be careful what you buy on ebay as there is limits to what the gear can do.The VagCom from RossTech is expensive but its all singing and dancing and can be updated and you can reset everything.
Rob
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Lifetime product support, updates to the latest version.
You can use it to code new modules, clocks etc. Also you can do live data logging to on the engine. You can code up certain features, alter parameters etc etc.
A handheld scanner will do most things icluding clearing codes as required.
Can the scanner do ALL of the above?
Yes VAGCOM is expensive but look at it this way. Every time you take your car to a garage or VW they charge you to look at it. Visit 3/4 times and VAGCOM has already paid for itself in diagnostic fees
Also you can earn beer tokens from anyone local to you