MB Speed detector sensor.

kmay

2013 Unity MB
MB likely has records on everything that MB shops have done to your RV. Make them pay.
In my experience, few of the MB service providers submit repair data to a centralized data base. I tried to get some investigative support from a service dept. in Buffalo and they saw just one of four prior service visits. The service advisor explained that there is a separate step involved in submitting data up the chain so many just skip this step or maybe do this on a slow day...there is no profit in this step.

My point in asking was an attempt to find a root cause. To date, none of the service providers have done anything to address why the WSS failed. The service advisor stated their policy and shop practice was simply respond to the code list, replace as needed and reset. There is no procedure, no billing code or authorization in their service documents to assess the system and diagnose why a part fails. While they acknowledged WSS failures are very high on RV up-fit Sprinters, there is no consensus on why within the Benz-verse. Theories are that there was a bad batch of sensors, maybe a short in the wiring harness or rear axle wear results in misalignment of the rear sensor. I was standing there with money in my hand and they sent me on my way with a platitude.

I found all my needed documents (managed to improve legibility of one faded receipt with copier settings) and am happy to present my local dealer with this packet. I plan to use the monies to fund an independent root cause diagnosis/repair. Likely Linden Engineering in CO. At this point, I will take advantage of the recall to replace all four sensors. but I have no belief in a lasting repair with these sensors.

I am more than a little curious as to why Daimler-Benz has offered to extend this warranty and initiate a recall of WSS. My tin foil hat guess is they are working on settling environmental litigation in part by demonstrating good faith compliance.
 

Mike DZ

2016 View 24V (2015 3500)
The service advisor stated their policy and shop practice was simply respond to the code list, replace as needed and reset. There is no procedure, no billing code or authorization in their service documents to assess the system and diagnose why a part fails.
This is not really surprising - in a mass market of consumer goods, shops get their highest profit by following the corporate procedure. Get enough information to comply with the level of proof required to declare a component "bad", swap the component, and be done. Only a few shops (not normally dealerships) will do extensive tear down and testing - no profit. Some components are shipped back to HQ to get a teardown and testing, especially high warranty failure items, but that is normally focused on ensuring owners and dealers aren't gaming the warranty system - part of corporate warranty cost containment. If the warranty item is actually failing at a high rate, information will flow from the warranty managers back to engineering. Depending on the levels of warranty costs, engineering may be tasked to actually diagnose and perhaps do a redesign. Organizations such as the NHTSA can do a little more to force the issue - if they find that it is widespread enough and has a significant safety impact.
 

WinnieView1

Well-known member
Ours is scheduled at a local dealer Monday for; rear wheel speed sensors replacement, MBUSA CAMPAIGN NUMBER 2021020026. We will post anything we learn after that unless they don't have the new sensors in stock yet.

Dealer called today and said based on VIN recall is still Pending and until it goes Active in their system they cannot replace the sensors.
 
I went in to my dealer today they said the recall and the parts we not active. They tried to push off the refund of previous repairs until then. I had them read the letter. They made a copy of my paid for repair receipt and said they would get back to me.
 

Mike DZ

2016 View 24V (2015 3500)
Why do you think the MB Sprinter recall only covers rear wheels? Don't front wheel sensors fail also?
I think that is probably what the data shows - probably lots more rears and worse symptoms on the rear for a select population. So the rears on upfitted and RV get the recall and everyone in the year grouping gets the 10 year warranty extension.
 

TwoClinks

2016 Unity TB
Thanks Mike. I think most of us would like the problem to go away by changing them all. My 2016 handled the failure OK. On the last rear failure, I had the dash lights and only loss of cruise control. So I just drove the Sprinter some 1100 miles back home to my familiar service center. It appears that the recall action doesn't have the parts available and that some of us will be on a call list when they do arrive.
 

Flexcor

Member
The recall information on NHTSA website mentioned moisture as a cause of premature failure ". An authorized Mercedes-Benz or Freightliner Sprinter dealer will replace the rear-wheel speed sensors against a variant with higher robustness against moisture intrusion. " Recall is only on RVs. Could it be that lack of a full wheel well on RVs allows more moisture to seep into sensor? MB logic being the front wheels have the standard sprinter wheel well and they do not have a recall able issue with other non RV sprinters . This is my theory.
 
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avanti

2022 Ford Transit 3500
The recall information on NHTSA website mentioned moisture as a cause of premature failure . Recall is only on RVs. Could it be that lack of a full wheel well on RVs allows more moisture to seep into sensor? MB logic being the front wheels have the standard sprinter wheel well and they do not have a recall able issue with other non RV sprinters . This is my theory.
Well, B-vans have standard rear wheel wells and, at least in my case, they are not immune from this issue. I suspect that the rears are more susceptible to moisture damage due to increased exposure to spray from the front wheels. It is also possible that long periods of sitting may help make RVs more vulnerable.
 

TwoClinks

2016 Unity TB
Yes avanti, my home MB shop indicated that there was corrosion on the sensor and caused failure. His recommendation was to drive and use it more. However 2020 it was tough traveling RVing due to Covid travel restrictions from one state to another, public & private campground reductions & shutdowns, and restrictions placed no local restaurants and attractions. So we never travel as much as usual. Now that the vaccine is available, we're ready to go. Digging deeper in our pockets for the higher cost of diesel fuel.
 

kmay

2013 Unity MB
Update, I submitted through my local Mercedes Service department required documentation of the six WSS sensors I have replaced to date. I had a sit down conversation with the service writer on another issue and asked him to verify receipt and proper submission of documents as well as current status of WSS reimbursement. He reports that Mercedes is "holding the reimbursement claims in pending status" and will pay out at a later date. So according to his info, no one has been reimbursed for WSS sensor replacement under this warranty extension.

When I informed the writer that I had replaced six sensors, his curiosity peaked and he starting rummaging in the data base. He found some, but not all the replacements.

I have a 2012 chassis so the clock is ticking down on the life of my WSS warranty.
 

WinnieView1

Well-known member
The recall appears to be "Active" now with parts available for the 3500 chassis' WSS replacement;

Ours is showing INCOMPLETE and we are scheduled for 2 weeks from now and will report our results.
 

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