So as I was driving home from work today about half way thru my trip home my s500 began to display coolant level low visit workshop I figured I'd buy coolant in the morning put it in the car. The whole time I'm riding home the car is fine. The temp is mostly normal wit a tiny bump up. When I pull onto my street it starts to go up more, as I pull in the driveway it now starts smoking and displaying BAS. I quickly tried turning the key to off but I was panicked so I think I left it in drive when i turned the key to off. When I did turn the key to off the engine kept running even as I pulled the key out of the ignition! Until it finally ceased after about 20 secs. Now I can't turn it at all and the dash lights are on and won't go off. Plus the engine is making this low noise almost silent. When I put the key in regular without a turn the radio works but I can't turn key and brake seems to be applied... Pleaseeeee helppppp!!!!!!!!!??????!!!!!!

 

You may have to replace your ignition cylinder.

How to Troubleshoot a Faulty Ignition Lock