1995 C280 engine not shutting off
 

Hi: My C280 (1995) engine does not shut up even with the ignition harness unplugged from the ignition switch. Plug terminals have voltage on both number 30's and on number 15 contacts. The curious thing is that all dashboard lights and functions stay on with the unplugged harness. Is there a shortage or a relay causing this? Where? Thanks to all!!!

This is either a faulty alternator or a failed diode in the instrument cluster. Try unplugging the alternator, if no change unplug the instrument cluster. If nothing works replace the OVP.