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BMW_Master, BMW Mechanic
Category: UK Car
Satisfied Customers: 5895
Experience:  Shop Foreman, 9 year Dealer experience.
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what is servotronic failure on a bmw 645 is it a big job

Resolved Question:

what is servotronic failure on a bmw 645 ?

is it a big job to fix ?
Submitted: 7 years ago.
Category: UK Car
Expert:  BMW_Master replied 7 years ago.



Can you clarify the problem a bit for me? The servotronic is power assist for the steering system. The typical failure on these is from the active sway bar and it gives a message of the vehicle tilting with an error message. Is this the situation you are experiencing?


Also, can you provide the last seven of the vin number as this will help with price estimates. Thank you.

Customer: replied 7 years ago.
The light and warning symbol is on when I start the car - says 'servotronic failure'. The power steering assistance does not seem to be on as the steering is very heavy.

last 7 vin no's are - B535155

Expert:  BMW_Master replied 7 years ago.

Thank you Gary. I will look into this in the wiring diagrams for the servotronic module. Most often this is an electronical failure.


It looks like the servotronic is controlled by the saftey gateway module. I have seen this module fail for various reasons.




This module needs programming to work correctly after replacement so the dealer will have to perform this. They would charge 1 hour to install the unit and aprox 1.5 hours for programming of the vehicle as we have to do the entire vehicle due to software.


Now this could also be related to the servotronic valve unit but this is not as common.





The only way to know for sure would be to run some tests using the BMW diagnostic equiptment at the dealer.


The cost for the safety gatway module that is most likely the failure is: aprox(NNN) NNN-NNNNdollars for just the part.


I hope this information is helpful.Please accept and please let me know if I can clarify anything for you. Thank you.


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