2013 E350 Seat Belt Pre-tensioner Issues….
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Super Member
Joined: Aug 2006
Posts: 545
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2013 E350 Seat Belt Pre-tensioner Issues….
Hi I got a question for all you guru’s on this board. Just yesterday my seat belt started acting up. It went through the pretension but for some odd reason didn’t retract so it was extremely loose on me. I figured I pull it slowly and it would start to retract but was wrong. So I kept on pulling it in increments and eventually got all the way out. Long story short pulled over down the street and was fully extended so I sort of gave it a yank and it started to retract. Figured all was good but now it wont pre-tension anymore. I can hear the motor but nothing. The safety feature of the belt appears to be working if I yank it hard enough it will lock. No errors on cluster. I’m thinking it probably just needs to be recalibrated or reseated? Not 100% sure and was wondering if anyone else encountered this?
Thanks in advance
Thanks in advance
Out Of Control!!
Joined: Apr 2019
Posts: 11,921
Likes: 6,769
From: Silicon Valley
W212 MY'14 M276-3.5NA @75kMi
safety first
What everyone is saying is... don't mess with it!
Belt pre-tensioners are built to be non-serviceable crash parts.
What DTC fault are you getting? These modules report and take orders on CAN-E1.
The safest way to go would be to replace the driver side with a part of your choice to restore safety. Any Dorman deal?
That being said I recall looking at that unit and deciding I was not going to trigger 1-way temper detections. I saw it's has a tiny belt with ribs like our electric steering rack. 3x bearings traveling on a plastic ramp are used to lock belt extension.
You can trust this German part to perform as designed and quit when supposed to. Hopefully codes will provide you with further info about what caused your troubles besides "replace faulty unit" -
Belt pre-tensioners are built to be non-serviceable crash parts.
What DTC fault are you getting? These modules report and take orders on CAN-E1.
The safest way to go would be to replace the driver side with a part of your choice to restore safety. Any Dorman deal?
That being said I recall looking at that unit and deciding I was not going to trigger 1-way temper detections. I saw it's has a tiny belt with ribs like our electric steering rack. 3x bearings traveling on a plastic ramp are used to lock belt extension.
You can trust this German part to perform as designed and quit when supposed to. Hopefully codes will provide you with further info about what caused your troubles besides "replace faulty unit" -
Last edited by CaliBenzDriver; May 15, 2022 at 11:04 AM.
Thread Starter
Super Member
Joined: Aug 2006
Posts: 545
Likes: 1
What everyone is saying is... don't mess with it!
Belt pre-tensioners are built to be non-serviceable crash parts.
What DTC fault are you getting? These modules report and take orders on CAN-E1.
The safest way to go would be to replace the driver side with a part of your choice to restore safety. Any Dorman deal?
That being said I recall looking at that unit and deciding I was not going to trigger 1-way temper detections. I saw it's has a tiny belt with ribs like our electric steering rack. 3x bearings traveling on a plastic ramp are used to lock belt extension.
You can trust this German part to perform as designed and quit when supposed to. Hopefully codes will provide you with further info about what caused your troubles besides "replace faulty unit" -
Belt pre-tensioners are built to be non-serviceable crash parts.
What DTC fault are you getting? These modules report and take orders on CAN-E1.
The safest way to go would be to replace the driver side with a part of your choice to restore safety. Any Dorman deal?
That being said I recall looking at that unit and deciding I was not going to trigger 1-way temper detections. I saw it's has a tiny belt with ribs like our electric steering rack. 3x bearings traveling on a plastic ramp are used to lock belt extension.
You can trust this German part to perform as designed and quit when supposed to. Hopefully codes will provide you with further info about what caused your troubles besides "replace faulty unit" -
Thread Starter
Super Member
Joined: Aug 2006
Posts: 545
Likes: 1
Out Of Control!!
Joined: Apr 2019
Posts: 11,921
Likes: 6,769
From: Silicon Valley
W212 MY'14 M276-3.5NA @75kMi
Ignorance is bliss 😊
Not getting any codes so thats a good thing! I’m pretty sure the unit is fine as is just doesn’t have that little tug during first buckle after starting the car. When I tug on it, it does lock. Retracts as normal so mechanically it functions just doesn’t have that tug as stated. Currently I just turned it off. Was annoying at first but sort of grew on me. Lol Anyways I’m thinking its just mis-aligned or fell out of place hopefully something that simple but probably not.
The published TSB was dated 2012. Your MY13 could be affected based on assembly month.
Match software numbers using your scanner for peace.
Thread Starter
Super Member
Joined: Aug 2006
Posts: 545
Likes: 1
You can just ignore this knowing your module is error free and works. I have had this friendly squeeze option disabled since early on.
The published TSB was dated 2012. Your MY13 could be affected based on assembly month.
Match software numbers using your scanner for peace.
The published TSB was dated 2012. Your MY13 could be affected based on assembly month.
Match software numbers using your scanner for peace.
