Obviously there are insurance issues if you had an accident and never knew the car was mapped etc .....

But what if you where told it was mapped and there is no receipt to prove how would you know for sure?

My engine light is on and I was told this was because it was mapped I suspect this is bollox but I had it checked by a mate after replacing a few bits we cleared the light it's came back on but with no codes would a map cause this if so would it be worth getting it mapped again to get the light off?