i know no fucker will post up on this but gunna ask anyway.

2 litre petrol galaxy.
fail mot on emissions due to lambda sensor being fucked, so replaced, and it drives a lot better and no flat spot, so alls well, but although it passed mot emissons were still high, was told it was fault code.
how would i clear it on the galaxy? been told disconnect battery which i was gunna do anyway and leave off for half hour, then someone said about turning ignition on and off a few times.

just wanna know if anyone has done it on a galaxy