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W906 SPRINTER NO CRANK, NO START

34K views 22 replies 8 participants last post by  lsalsbery  
#1 ·
I have problem with a 2011 Sprinter, with a no crank, no start. Absolutely nothing happens when the Ignition switch is the position 3 (start), No click, Nothing. Have checked everything out and nothing shows up on my Star diagnosis. Can get the engine to turn over by grounding out the respective terminal on the starter relay, so the ‘live side’ of the starter system works OK Gear selector moves and shows positioning on the dash and as it moves between P R N D L. I think something between the ignition switch and the next thing on, whatever it is, (it is obviously not direct to the starter solenoid). The thing I am trying to find out, (which you would think would be so simple to get answered, but even my local M-B dealer can't), is what terminal / wire color on the ignition switch should become live (or ground) when the ignition is in position three (Start). Something must go somewhere from the ignition switch when in the start position, but with the electronic nightmare, box of tricks, ignition switches are nowadays, nothing can be seen by taking it apart. Anyone any suggestions?
Switch works perfectly in positions 1 and 2 with all lights coming on and then most going off after some seconds. Even the engine management light goes out and stays out after the engine has been turned over by grounding out the starter relay terminal.
 
#7 ·
Hey mate, yeah so we’ve ordered a new ECU still waiting on it from Germany, but a bit of background the EIS sends a CAN signal to the ECU which then closes circuit 50 (inside the ECU) which can then actuate the starter relay in the SAM, will keep you posted once we’ve fitted our ECU :)
 
#10 ·
I had a same problem with 2008 Sprinter and just pick it up from my mechanic which almost 98% he works on sprinters
What we found out is that the control module on ignition and steering column lock will let the key to activate and even diesel pumps to run u can hear it but no crank then his MB system guy run a check on ignition sequence and one of the can bus locks was on which will let the key to turn but won’t let the starter to turn
After a couple times he reset the sequence and the. We had a crank and start
My sprinter was out of service for about a year and a half cause we couldn’t find a solution
We even change the entire engine harness and swap computers for both transmission and engine and still wouldn’t crank
I hope this will help and like I said check ur ignition sequence on MB computer then check all from top to bottom of the screen if it check out
Good lock
 
#21 ·
First post on this thread. Very Interesting, Dealing with no crank no start as well. no codes on MB star or launch or autel scan tools. Tried everything suggested here today before I read this forum (faceplam). I have two other sprinters to refer to. tried disconnecting tcm. for some reason EGS would not shift gears when TCM was disconnected, this is entirely not the case on other van which can start and drive with tcm disconnected ( though not shift out of second gear of course). easy way to test this park/neutral contact circuit I believe would be to simply unplug fuse seven under driver's seat. of course if you are like me you will just pull the conductor plate and run a continuity test on the Reed switch only to find it works perfectly for no reason at all ( facepalm). BTW the service manual suggests to replace entire valve body if this issue does come into play, any rational reason for this? while I am ranting how can a no crank issue be caused by ECM? My other sprinters crank all day with ECM removed.