I have a 2002 W210 which has developed a strange electrical fault. Above 65mph the abs/esp/bas light blinks on and off intermittently with the usual 'visit workshop' warning. After a while it clears itself and the abs/esp/bas functions as normal as I've checked it out. Below 65mph this doesn't happen until I turn on the headlights!! The headlights come on, the abs/esp/bas lights blink on and off and then the offside zenon headlight goes out, providing me with a new warming of a failed lamp. Mercedes haven't been able to provide a conclusive answer and have suggested either a new car battery or an earthing fault in the headlight/sidelight switch......either way they want me to spend more money on investigations and I'm fed up doing that now! Mercedes don't believe I have a faulty abs sensor, which I guess is some good news. Any suggestions would be gratefully received.