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Marty, ASE Certified Technician
Category: Mercedes
Satisfied Customers: 54950
Experience:  Bosch Certified Master Technician with over 35 years experience in the automotive industry.
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B200 5 door MB. The front door lock just chatters when I

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B200 5 door MB.
The front door lock just chatters when I press the key but will not lock. Sometimes I can press down to lock
Took car to MB but they want 550 pounds to replace parts =
Please advise me what parts I need as I can do the fit myself - as I do all my own engineering on several cars.
Max Fletcher
Hi Max, my name is***** you post your 17 digit chassis number for me?
Customer: replied 3 years ago.

WDD245233 2J 023362 [9]

this number is ***** the engine space plate. The is another 17 digit number [Getriebe] but it only in the manual.

It does appear to me that this car has a locking solenoid [ due to the chatter when the locks come on- [not an air system] but as I have not had the door card off I wait your expertise. All the other locks work perfect.



Hi Max, yes this problem is caused by a faulty door lock actuator. The part number for the left door is 169 720 43 35 plus an additional boot, part number 169 723 00 94 is needed. The part number for the right side door lock actuator is 169 720 38 35.


Let me know if you have any questions.

Marty and other Mercedes Specialists are ready to help you
Hi Max, I'm just following up with you on the Mercedes. I see that this question is still open. Do you need anymore help with this? I can provide you with the workshop instructions for replacing the door lock if you need them.

Please let me know.