I bought my 2001 SLK320 last year ,It had been sitting for five years it was park because of a minor fender bender which I repaired. After replacing the fuel pump , fuel filter, new spark plugs , and coil packs , car ran fine .The only other problem was the radio was stuck on mute so I had to replace with a aftermarket radio , and the pse pump had been disconnected because the driver door actuator was bad .I bought a new one but didn't replace yet because it didn't seem that important right since car was running so well .And the key would hang a little ,but if I flip it over it would turn just fine, Bought 2 new keys from the dealer but it didn't change that problem , but car would turn over and start. I drove the car for six mouths no problem and then came the NO START ERROR. The message would flash when you turn the switch to position 2. and the cooling fan would run wind open . If you let it sit for a few hours it would start up, but if you cut it off it would not restart . But now it wont start at all,all of the instrument lights are on and cooling fan running. I checked and cleaned all the fuses and sockets .Checked and resoldered the K40 and bought a new K40, New battery, checked the grounds check the ECM , Starter relay and immobilizer for oil or burnt connections...???could a bad starter intermittingly give a no start error , any ideas appreciated

 

As a thought- Have you checked the Crankshaft Position Sender? I had a similar problem. Replaced sender, Fixed.. My 2 shillings worth..

 

still fighting this no crank /no start error ,, replaced transponder, transponder ring , eis, k40, fuses good starters good. Looks like all thats left is the ECM,

Does anyone know if using a ECM service is safe , I see a lot of bad reviews, looks like my last resort, other than the dealer