Thanks for that Tabetha, I will try that one, the mechanic replaced the one in front of the CAT but not the one behind the cat? The light went off today when I started up, then came on again once it had warmed up on the motorway, it seems to follow that pattern, once on, it will stay on for about a week. It still runs like a dream, if I disconnected the light, you would never know there was anything wrong, course I would never do that................