Ask an expert

Oh dear, just bought a Mazda Demio today (AA presales check done on Friday) and woops, driving home the engine warning light comes on. Is that bad luck, or what?

Not sure what it could be. On-line search found someone who says check the petrol cap, and I did buy some petrol before the trip home. The cap seems fine, but could something like that be the cause?

Also on-line, a suggestion to disconnect the car battery then reconnect (might reset the indicator). Should I try that?

Any advice?

Hi there,
This check engine warning light means that a sensor monitoring the engine operation has
malfunctioned. Call the dealer right away and ask them to sort it. It requires a computer diagnostic to read the code and pin point the fault, this can be done at a dealer or workshop.