L6/3 Left rear axle rpm sensor has a mechanical fault

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@dogday , weird looking log, I would have thought that if you get a signal, then the sensor is working and the fact it varies so much indicates a non uniform reluctor ring...
were you still having issues because of the variance?

I went and bought the socket, spline bit, additional spanners (they were shiny...) and a 10 hex bit (didnt really need that as I could have cobbled one together from a torx kit I have)

Trying to book some ramp time, there is a place in Sheffield and perhaps Donny that rent out ramp time but I'm looking closer to home if possible

Oh and also bought a reluctor ring from GSF.

I bought the Creader Elite Benz version which seems fairly conmprehensive with a few minor issues - it variously identified my car as either correct Mercedes E350CGI, then as you drill down it swaps id to a Long wheel base E180 Sedan or a Maybach E350 CGI! I think their latest software may have fixed that but still need to try it drilling down into various systems.
What it didnt do, and Im still not sure if its fixed, is calibrate the rear ride height - it dropped it on its ass last time and it took some jacking up to get it into the range it would trigger the comp to re-pressure the bags!

Every day is a school day.

If I get a ramp, I'll change out the rhs airbag at the same time.
 
@dogday , weird looking log, I would have thought that if you get a signal, then the sensor is working and the fact it varies so much indicates a non uniform reluctor ring...
were you still having issues because of the variance?

I went and bought the socket, spline bit, additional spanners (they were shiny...) and a 10 hex bit (didnt really need that as I could have cobbled one together from a torx kit I have)

Trying to book some ramp time, there is a place in Sheffield and perhaps Donny that rent out ramp time but I'm looking closer to home if possible

Oh and also bought a reluctor ring from GSF.

I bought the Creader Elite Benz version which seems fairly conmprehensive with a few minor issues - it variously identified my car as either correct Mercedes E350CGI, then as you drill down it swaps id to a Long wheel base E180 Sedan or a Maybach E350 CGI! I think their latest software may have fixed that but still need to try it drilling down into various systems.
What it didnt do, and Im still not sure if its fixed, is calibrate the rear ride height - it dropped it on its ass last time and it took some jacking up to get it into the range it would trigger the comp to re-pressure the bags!

Every day is a school day.

If I get a ramp, I'll change out the rhs airbag at the same time.
I have only replaced the sensor so far and not the ring so the graph does seem to point to a gap in the ring ?

The tool sizes used by Mercedes seem to be different to those used by other manufacturers. Generally they have been 17,19 and 21mm for other cars. I attempted to replace the ring yesterday but my car jack started to buckle and a 3ft wrecking bar on the hub nut failed to budge it so might have to get a garage to do it. At 320Kn torque to tighten the hub nut, a stuck hub nut and possibly a stuck axle in the hub and an inferior tool kit makes the possibility of using a garage seem more likely :(

Where is the ramp for hire in Sheffield? I live about 10 miles West of Hillsborough.
 
Think I’d try to loosen the hub nut with the wheel on and resting on the floor
 
Think I’d try to loosen the hub nut with the wheel on and resting on the floor
That's what I did. Stood on the wrecking bar, put an axle stand under the wrench so it wouldn't twist on the nut and still wouldn't budge. A length of scaffold pole would have helped if I had a piece. Notice Screwfix have got a discount on impact drivers.

Ta for the info about the ramp.
 
It's not a left hand thread on that side is it??
 
It's not a left hand thread on that side is it??
It's a possibility I suppose. However, as the nut is tightened to 320Kn it's probably not surprising that the nut is a bit tight. Just watched a video of somebody undoing the rear left nut on a W211 where they had to use a 6ft scaffold pole on the end of the rachet and that was 'normal' anticlockwise to undo. All of my old cars were tighten the nut then slack off half a turn so they were easy to remove.

Maybe a cheap 1/2" impact driver would do the job. Has anybody managed to undo one of these nuts with an electric corded or cordless impact driver?

Has anybody an idea of how many hours a garage would charge to replace the reluctor ring?

Just checked autodoc and they don't sell separate left or right threaded nuts, just right threaded.

Thanks
 
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It's a possibility I suppose. However, as the nut is tightened to 320Kn it's probably not surprising that the nut is a bit tight. Just watched a video of somebody undoing the rear left nut on a W211 where they had to use a 6ft scaffold pole on the end of the rachet and that was 'normal' anticlockwise to undo. All of my old cars were tighten the nut then slack off half a turn so they were easy to remove.

Maybe a cheap 1/2" impact driver would do the job. Has anybody managed to undo one of these nuts with an electric corded or cordless impact driver?

Has anybody an idea of how many hours a garage would charge to replace the reluctor ring?

Just checked autodoc and they don't sell separate left or right threaded nuts, just right threaded.

Thanks
Well, it was sunny today(at least when I started) so I set to, more so to see how far I could get regarding loosening fasteners etc.
I had the wheel off and knocked out/back the retaining collar of the nut then refitted wheel lowered to ground and managed to loosen the nut using just a 600mm bar and the socket I bought yesterday. It clearly gave less of a fight than yous did
Removed all bar the bottom arm bolts without too much problem then judicious tap with a soft faced hammer then I used a two legged puller that was home made a couple of decades ago. Hey presto!
I was surprised how simple it was to get apart tbh. Swinging the hub down, allowed the shaft to be extracted and there in all its glory was the knackered reluctor ring. The magnetic rubber part had separated from the metal.
Good clean up with wire brushes etc and tapped on the new reluctor, reassembled without a lot of difficulty, hampered only by the rain that showed up!

Anyway, codes cleared and the problem still exists which was half expected as I still have a suspect replacement sensor, need to order one and will try a Pagid from euro car parts which if that doesn’t sort it will bite the bullet and get one from Mercedes..

A side note, having bought the 16mm ratchet spanner and the 10mm hex, found that my existing 16mm spanner sufficient for the drop link from the sway bar and failed entirely to find where I might have used the 10mm hex. Most all the bolts were M12 spline one end and 18mm A/F the other.. I would recommend an 18 ratchet.

I can confirm that it’s a lefty loosely, righty tightly… no lh threads found

I’ll update when I get the new sensor.
 
When my abs sensor was suspect I bought one from EBay, Febi version for £25, worked perfectly, but didn’t cure my problem as it turned out to be the magnetic wheel bearing, instead of a reluctor ring it picks up pulses from a magnetic seal in the bearing.
 
When my abs sensor was suspect I bought one from EBay, Febi version for £25, worked perfectly, but didn’t cure my problem as it turned out to be the magnetic wheel bearing, instead of a reluctor ring it picks up pulses from a magnetic seal in the bearing.
Looking on the autodoc site it looks like only the front wheels have bearings with a built in ABS magnetic ring. I have also read that these bearings have to be fitted in one direction only otherwise they don't work.
 
Well, it was sunny today(at least when I started) so I set to, more so to see how far I could get regarding loosening fasteners etc.
I had the wheel off and knocked out/back the retaining collar of the nut then refitted wheel lowered to ground and managed to loosen the nut using just a 600mm bar and the socket I bought yesterday. It clearly gave less of a fight than yous did
Removed all bar the bottom arm bolts without too much problem then judicious tap with a soft faced hammer then I used a two legged puller that was home made a couple of decades ago. Hey presto!
I was surprised how simple it was to get apart tbh. Swinging the hub down, allowed the shaft to be extracted and there in all its glory was the knackered reluctor ring. The magnetic rubber part had separated from the metal.
Good clean up with wire brushes etc and tapped on the new reluctor, reassembled without a lot of difficulty, hampered only by the rain that showed up!

Anyway, codes cleared and the problem still exists which was half expected as I still have a suspect replacement sensor, need to order one and will try a Pagid from euro car parts which if that doesn’t sort it will bite the bullet and get one from Mercedes..

A side note, having bought the 16mm ratchet spanner and the 10mm hex, found that my existing 16mm spanner sufficient for the drop link from the sway bar and failed entirely to find where I might have used the 10mm hex. Most all the bolts were M12 spline one end and 18mm A/F the other.. I would recommend an 18 ratchet.

I can confirm that it’s a lefty loosely, righty tightly… no lh threads found

I’ll update when I get the new sensor

Good job! Hope that the new sensor finally sorts the problem. It sounds like everything come apart fairly easily. Why was the puller required? Was the axle stuck in the hub too tightly?
 
@dogday , puller probably not required but it was in the cupboard and seemed to be a little more civilised than braying it with a sledge hammer.
I've got so much crap in the garage as I'm a bit of a hoarder (tools wise). The hammer/mallet I used is a vintage, quite heavy copper one side/ rolled hide the other, seems to give more of a 'dead-blow' than a steel hammer.
If it gets above freezing today, I'm going to re-verify the connections and swap the (working and original) LHS sensor to the right to establish if the new reluctor ring is giving the correct signal.

Point of interest, the Metzger sensor, it was MEZ0900977, I bought from GSF was correct fit but had a different Merc part number and looking at Autodoc website, they list 3 different Metzger sensors:-

09001471 @£26, Version AM (after market??) OEM reference A2125402117 for SA codes 800/801/802/803

0900977 @£60 (same as GSF) Oem ref A2129053603/ A2129051001 NOT for SA 800/801/802/803!!

0900218 @£64, Version OE, Oem ref A2125402117 for SA 800/801/802/803

I didn't know what the SA codes were but found it relates to model year, with the last digit meaning 2010/2011/2012/2013, so it would seem the only sensor GSF offer is not for my year!

Looking at the other sensors offered by Autodoc(with correct A2125402117 ref) shows the sensors are 'active' and from reading elsewhere, these are not able to be/ should not verified by simply measuring resistance for continuity - it all gets very confusing.

If I order from Autodoc, anyone know how long delivery is typically?
 
If I order from Autodoc, anyone know how long delivery is typically?
When I ordered my sensor on a Saturday it arrived on Thursday. Their contact address is in Berlin. There were no postal strikes at the time.

If you can find the part on Amazon then that would be the quickest delivery.
 
Amazon, for a recognizable brand part is promising dispatch within 4-6 weeks!
 
Amazon, for a recognizable brand part is promising dispatch within 4-6 weeks!
Blimey !! I think Jeff might want to know about that. I'm going to have another go at my car tomorrow. Have you fixed your ABS fault yet?
 
Not yet, I had bought the Launch Creader Elite Benz to be able to calibrate the suspension, it was this that indicated WSS problem on rear rhs.
Couple of issues with it (its good but has flaws) had the vendor refunding most of the cost and allowing me to keep it. They refunded immediately so I used that to buy an OEM sensor from the local dealership in Harrogate, pee'd down yesterday so its not been fitted yet. Oh, for a decent sized garage!!
Visitors this weekend so unlikely it'll be done imminently, I'm going to allow a couple of hours which sounds stupid but I have doubts that it'll be plug in/job done. If it is, bonus and I might swap out RHS suspnesion bag...
I'll keep you informed
When my abs sensor was suspect I bought one from EBay, Febi version for £25, worked perfectly, but didn’t cure my problem as it turned out to be the magnetic wheel bearing, instead of a reluctor ring it picks up pulses from a magnetic seal in the bearing.
@geoffus , curious to know how Febi one worked perfectly - did it prove itself after you changed the bearing/mag ring? The original merc one cost me £116 after I pushed a bit on price. It did come in a very impressive , unnecessarily large box...
 
Not yet, I had bought the Launch Creader Elite Benz to be able to calibrate the suspension, it was this that indicated WSS problem on rear rhs.
Couple of issues with it (its good but has flaws) had the vendor refunding most of the cost and allowing me to keep it. They refunded immediately so I used that to buy an OEM sensor from the local dealership in Harrogate, pee'd down yesterday so its not been fitted yet. Oh, for a decent sized garage!!
Visitors this weekend so unlikely it'll be done imminently, I'm going to allow a couple of hours which sounds stupid but I have doubts that it'll be plug in/job done. If it is, bonus and I might swap out RHS suspnesion bag...
I'll keep you informed

@geoffus , curious to know how Febi one worked perfectly - did it prove itself after you changed the bearing/mag ring? The original merc one cost me £116 after I pushed a bit on price. It did come in a very impressive , unnecessarily large box...
Yes I changed it to the right hand side to prove it worked fine, there was nothing wrong with the sensor in the end as the original one worked as well, the fault was the magnet seal embedded in the bearing.
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Yes I changed it to the right hand side to prove it worked fine, there was nothing wrong with the sensor in the end as the original one worked as well, the fault was the magnet seal embedded in the bearing.
Was that on the front wheel?
 
Was that on the front wheel?
Sorry, yes it was.
 

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