Hi if i remember correctly the esp cuts engine power and triggers abs/brakes in the event of a stability problem such as a slide or skid. Would suggest a quick plug in of diagnostics to tell you what the prob is but a couple of things come to mind, a dodgy abs sensor on a wheel or an engine problem and the esp light has come on to warn you esp is unavailable.Hope that helps but a diagnostic is the only way to really tell. Hope you live near someone with a laptop or reader as Frauds charge about 65 quid.