Will not crank


The starter got stuck yesterday and kept cranking after the engine started. I shut the engine off and restarted. All was fine. Went to restart later and not it will not crank.
My first thought was that it was a starter solenoid issue. Not being able to replace just the solenoid, I replaced the starter. Yes, I should have bench tested the starter but ..... Engine still will not crank.
Anyone have a suggestion how to proceed?

Fabio Daniel


You were dead lugnuts on! Mucho Thanks.
When I pulled the back cover off of the K40 relay it was obvious where a component had failed and fried the circuit board.
The part number is A 000 540 00 72 and was in stock at MB with a retail price of $111.63. BTW this appears to be the part number for most/all W210s. It took all of 10 minutes to replace.
Here's a pic of the bad part. Note the copper section which got hot, burned off the green top layer, lifted off the board, and finally melted the copper in half.
Last edited by John H; Nov 12, 2010 at 02:00 PM.
hope it help you bro! let me know any news
at your order my friend!
PD: Bro i see some white sulfite marks in the green board, check the proper fitment of the box module cover to not entered any water.. hot modules without proper closed box produce some evaporation & appers this marks burning relays, modules, etc. check too inside the EGS module if you not have any trans oil inside, some cases oil inside the EGS burns the relay box
Fabio Daniel
Last edited by Fabio D; Nov 12, 2010 at 08:15 PM.


Thanks again!
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Nope because your car is cranking. The relay problem is this thread prevents the car from cranking. The Crankshaft position sensor will prevent the engine from starting. Common problem on the w210 and on Chrysler Jeep vehicles
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not crank and the K40 relay looks good
Battery is im good conditions



