I've seen this problem seems oftenly happened in the vw. So here come my version =
My car is touran 1.4 twincharge. I am using racechip pro.
This messages : ''brake servo fault'' several times shown in My MFD. Randomly. What I done if this happened is =

1. Stop the engine
2. Unplug the racechip, then plug it to the ''dummy'' chip
3. Start the engine. Walks the car few meters. The problem gone in the MFD and abs lights
4. Unplug the dummy. Plug the racechip again.
5. And all fine.

This ''brake servo faults'' msg comes randomly every at least once in two month. And if this happened, I do procedure as above.

Any toughts what is happened?

Thank you.

It's not a volkswagen, it's just a car