RE: SLK320 won't start
Hi, Still stranded?
Your original post did not include the bit about the dash message.
As a consequence I now agree with Sleepwalker.
Did the Lock/Unlock help? Did you use the real key or the remote fob to gain access to the car?
When you get the "Heavy Click" when trying to start do the headlamps / interior lamp/and dash lamps remain bright? If so this significantly reduces the possibility of a bad battery.
Sounds like the DAS (Driver Authorisation System) but why has it gone bad? I need to check whether the DAS is linked to the transmission lock. I guess it will be. I will also look to see if the DAS has a unique fuse but I wouldn't have expected this.
Sure you have the correct keys? You don't have two MB's by any chance and hence the wrong key since the DAS must receive the correct digital signal from the key.
Do the doors OPEN/CLOSE with the REMOTE operation on the key fob? The DAS radio receiver is common to the door operation and the engine inhibit. If not, are the batteries OK.
"Can't get it out of park" .....Sure you have the IGN and Footbrake ON?
How old is the car? Since it is a 320 it must be the older model. Age? Mileage?
Any other bits of data. Has the weather been very wet?