2002 Renault Scenic intermittent starting

hi there, it may seem to be an immobilizer problem. renaults do suffer from decoder ring trouble thus giving intermittent start problems. the first thing to do is try starting the vehicle with the spare key. if fault persists, then seek a replacement decoder ring from your local renault dealer and fit. its a simple job 20mins is more than enough. if after that the problem is still there, then i'm afraid its off to renault to have the systems checked... hope this helps!!!

What do you think the problem may be if it wont start at all? It has happened to my mum's car about 4 times in the last six months, she has to get it towed everytime to the garage and they keep telling her they cant find anything wrong with it and return it to her running every time, would this also be an issue with the decoder ring? Her model is a six yr old 1.4 petrol? I would greatly appreciate any advise on this :-)