Chris M. White <cw9877@gsm.com> wrote:
Guys,
I have an aging (18 year old) Mercedes W211 which has developed a
fault which is causing the dash to light up like a Christmas tree.
This one fault is causing 3 different warning lights and associated
text warnings to come up: ABS, ESP and SB. I took it to an independent
garage that specialises in Mercs and has all the software etc. Turns
out the problem is a magnetic ring buried deep inside the n/s rear
stub axle. The part costs peanuts, but is *murder* to get at. Even for
a Merc main dealer it's half a day's work and requires several special
service tools. I was quoted over 500 quid to fix it! +VAT!!
So I've come up with an ingenious work-around I'd like to run past you
all; see if there's any adverse consequences I haven't thought of. The
car's main CPU thinks the rear n/s wheel is losing grip, because it's
sensing (wrongly) that the speed of that wheel is diffrerent to the
speed of the one on the opposite side. How about I snip the feed from
the n/s sensor and connect it in parallel with the feed from the o/s
one? That way, the CPU will see the signals as perfectly in synch. The
sensor on the 'good side' stub axle will then be supplying speed info
for *both* sides and the duff side will be snipped out of circuit
altogether.
Your thoughts on anything I haven't considered (I mean *technical*
issues, not daft observations about legality etc.) I would remind you
all there are plenty of classic cars on the road that don't have ABS
at all so it's not inherently dangerous.
Probably not as issue on a vehicle that age but I imagine that might upset any stability control software (or at least stop it working properly).
Whilst I take your point that many older cars didn’t have ABS, I think as far as MOT is concerned, if it was fitted, it has to work.
Might be worth getting a second opinion on the work involved. Hard to
believe that any work on a stub axle can be that complicated. Have you searched YouTube?
This any help? https://youtu.be/-LZFH3npitg
Dunno about that particular Merc, but its unlikely to
be a simple analog signal that you can do that with.
Guys,
I have an aging (18 year old) Mercedes W211 which has developed a
fault which is causing the dash to light up like a Christmas tree.
This one fault is causing 3 different warning lights and associated
text warnings to come up: ABS, ESP and SB. I took it to an independent
garage that specialises in Mercs and has all the software etc. Turns
out the problem is a magnetic ring buried deep inside the n/s rear
stub axle. The part costs peanuts, but is *murder* to get at. Even for
a Merc main dealer it's half a day's work and requires several special >service tools. I was quoted over 500 quid to fix it! +VAT!!
So I've come up with an ingenious work-around I'd like to run past you
all; see if there's any adverse consequences I haven't thought of. The
car's main CPU thinks the rear n/s wheel is losing grip, because it's
sensing (wrongly) that the speed of that wheel is diffrerent to the
speed of the one on the opposite side. How about I snip the feed from
the n/s sensor and connect it in parallel with the feed from the o/s
one? That way, the CPU will see the signals as perfectly in synch. The
sensor on the 'good side' stub axle will then be supplying speed info
for *both* sides and the duff side will be snipped out of circuit
altogether.
Your thoughts on anything I haven't considered (I mean *technical*
issues, not daft observations about legality etc.) I would remind you
all there are plenty of classic cars on the road that don't have ABS
at all so it's not inherently dangerous.
Might this be CAN bus?
Guitar pickups have a magnet in the coil. No need for rotating magnets - just teeth on a sensor ring going past will do the job
On 31/07/2021 08:46, Peter Hill wrote:
18mm bolts wtf?
On Japanese cars they're 2 a penny, and they also like Metric fine
threads. Though to my knowledge 18mm isn't an ISO standard.
On 29/07/2021 21:26, alan_m wrote:
On 29/07/2021 21:00, alan_m wrote:
On 29/07/2021 20:30, Chris M. White wrote:
Guys,
I have an aging (18 year old) Mercedes W211 which has developed a
fault which is causing the dash to light up like a Christmas tree.
This one fault is causing 3 different warning lights and associated
text warnings to come up: ABS, ESP and SB. I took it to an independent >>>> garage that specialises in Mercs and has all the software etc. Turns
out the problem is a magnetic ring buried deep inside the n/s rear
stub axle. The part costs peanuts, but is *murder* to get at.
Is the wire to it on a connector located near the stub axle? If so
is it a fault with the sensor or just a bad connection or corrosion
in the connector?
Youtube
https://www.youtube.com/watch?v=-LZFH3npitg
the £500 repair
https://www.youtube.com/watch?v=Xsqy8TeEcA8
Be about right at £125/hr. It's at least a 4 hour job and as the camber
and toe adjusters are removed it needs an alignment job.
18mm bolts wtf?
The M12 tri hex bit is available from machine mart in a set with M10,
M12, M14, M16 and M18 bits. I found that out doing rear brake discs on
my bothers Audi A3 after I had bought a Draper set of tri-hex, torx and
hex bits that only went up to M10.
Yet another reason to never buy a newer car.
| Sysop: | Keyop |
|---|---|
| Location: | Huddersfield, West Yorkshire, UK |
| Users: | 296 |
| Nodes: | 16 (2 / 14) |
| Uptime: | 85:36:57 |
| Calls: | 6,658 |
| Files: | 12,203 |
| Messages: | 5,333,708 |