Hey guys so I have quite the weird problem on my 2009 c300. One day I got in to start my car and it wouldn’t start. At first it would crank but no start, then eventually it just stopped cranking altogether. I went and replaced the battery and starter already as well as the fuses and it still won’t crank at all. When I put my key in the ignition my steering wheel comes down and all the lights on the dash come up but still no start. All the inside functions of the car operate normally like the windows, radio, and lights. The only thing that happens when I try to start it is I can audibly hear my starter spinning but the solenoid doesn’t actually engage. (And no it’s not a bad starter solenoid I just bought a brand new starter and tested it before installation.) So what I’m wondering is what could be causing my starter solenoid to not engage if I already replaced it and checked the terminals connecting to it?

Happy holidays,
Sterling.

 

moved to W204 forum...

 

I recommend you get your own Mercedes-specific scanner, such as iCarsoft MB V3.0, LAUNCH Creader Elite BENZ, or Foxwell NT510 Elite so that you can scan your car at any time. In the US, they are pretty inexpensive, well under $200 on Amazon. They are small enough to store in your car (such as the fuse compartment in the trunk). Sometimes a code may cause the car to run rough and clearing it will restore normal operation until you get a chance to check it out. (Do not waste your money on the iCarsoft MB II. It is slower and requires you to check each module for codes. MB V3.0 runs an automatic scan and will identify modules with DTCs so you don't need to check 30 or 40 modules individually.)

Once you get one, scan for codes and tell us what they are if you have any.
Where did you get your starter and is it genuine or OEM? Is it installed correctly? If it moved the gear and spun when you tested it outside of the car, but doesn't engage the flywheel, I can only guess it is not fully seated or it is defective.

 

I guess im a little confused when you say "I can audibly hear my starter spinning but the solenoid doesn’t actually engage..".

The solenoid is what basically gets the starter working. If you can hear the starter spinning/working but it doesnt rotate the engine there may be an issue with the pinion gear.

heres a photo i just pulled off the web, its not a Mercedes starter.



I dont have much experience with starters except for replacing two bad starters in previous cars. With those i heard the clicking noise but no start, so replaced the starters and it fixed the issue. With your issue it may be the starter. What kind is it, Mercedes? Who installed it?