Guide
Chiptuning and your warranty
The short answer you read everywhere is that your warranty is void. That isn't quite right, but it also isn't the case that nothing is going on.
Warranty doesn't lapse automatically
A manufacturer can't simply withdraw a warranty in its entirety because something on the car has changed. What it can do is refuse a repair if the damage was reasonably caused by that change.
If your air conditioning fails after a software adjustment, the two have nothing to do with each other and it should be covered as normal. If your turbo fails, it becomes a discussion.
What the discussion is about
In practice it comes down to who has to prove where the damage came from. Dealers often assume the tuning is the cause; you would then have to demonstrate it was something else.
That's difficult and it takes time. It's the main reason to think carefully before having a car that's still fully under warranty modified.
What a dealer can see
More and more manufacturers record how often the engine software has been written, and with what equipment. That happens automatically on read-out. Even if the original file has been neatly restored, that counter stays put.
Anyone telling you a dealer can't see it is telling the story of ten years ago.
What you can do
If your car is still under manufacturer's warranty and you don't want the risk, wait until it expires. If it has just run out, this no longer applies.
If you want it anyway, make sure you have the original file. Then you can go back to factory settings before taking a problem to the dealer — that isn't watertight, but it helps.
- Ask whether the original file is kept, and for how long
- Ask for a copy for yourself
- Ask what reverting costs and whether it's free within a set period
We read out the original file before changing anything and keep it for two years. You get a copy on request, and within thirty days we restore it free of charge.