I've scrolled through a million threads and on different web sites and found a world of different but vaguely similar advice
Makes me wonder if anyone really knows the secrets of the d2 abs black magic box??
so far I've done
new brakes shoes rotors
new hubs
option b
New sensors
Long leads to ecu

All part of a long list of jobs that forum has helped me through air suspension side steps swivel joints new rubber
Auto box flush refil and seals etc etc

and now they are back might have been caused by taking sensor out to replace cracked wheel bolts but maybe not ??

Lights on and reader says low sensor output and error code 0440
Looked at voltage from offending wheel nsf
I understand we want 0.9 volt but it’s ac none of my meters read this ?
Friendly lr tech says voltage a waste of time due to a number of issues not least meters
Is this true or how does it get measured I have car up meter connected to sensor wires turn wheel nothing showing on all three sensors I’ve tried
Aids law Fault has obviously happened in time for mot and now its failed and off road

I have replaced the sensor again checked the resistance 1,0 so within tolerance
have removed wing based socket and fitted a long sensor lead straight into slabs
all no difference


Looking through sensor hole there’s blue grease on the reductive ring
JGS very helpful who sold new hub 12
Months ago say it should be clean dry no grease
A number of posts here say grease no problem or even put some on - which is it ?

Brake System works fine mechanically but if lights come on at retest I'm stuffed
using I soft v 1 to read and clear faults
lights kick in at about 10 mph with the warning sound
asking you patient old ones if theres anything I've missed or I can do now except wire it to the oil light (only half joking)

Such a shame that a great car is heading to the big recycle bin unless I get this sorted
thanks

Tim

Someone may come along and correct me, but I'm pretty sure there's no AC on a vehicle, other than the wrong side of the alternator

So is the sensor output dc ??
I’ve read umpteen posts that say the current generated by refactor ring interrupting magnet in sensor creates ac my physics not good enough to know science but it rings a bell
Then the bigger air gap or dirt reduces the interior and voltage drops so fault appears

It’s not magic How do we help each other get and store definitive answers so we don’t have to trawl through a mush of conflicting stuff ?

You're right! Sorry i had no idea.. it will essentially be a hall effect sensor i think, which is indeed AC output
You're right, as the sensor gets further away from the reluctor ring then the voltage will drop causing an error
A DVM should have an AC setting, i know mine does

Mine, when I had one, turned out to be the front offside wheel bearing.

Sorry to be thick is Dvm you’re reader I’ve got icarsoft v1 can’t see ac voltage on it but will look again
There is a km reading from each wheel of 1.7 all four the same when car is stopped maybe this is voltage indicator somehow
In which case if I have good voltage or the same from all four sensors why is the slabs saying low voltage on nsf do I need to sort slabs
Have also just asked west 4x4 a local garage with a great rep

Let’s see

Any comments help welcome

Bw
Tim

Thinks Can’t be voltage as car is stopped

Maybe I should buy an old defender with no wires in it ?

DVM is a digital volt meter

tim Powell said:

Thinks Can’t be voltage as car is stopped

Maybe I should buy an old defender with no wires in it ?

Click to expand...

How much did you pay for the hub?
Oh and the icarsoft v1 is pretty much useless for the td5. The land rover version is much better but still not a patch on the nanocom or Hawkeye.

Apparently the sensors are very sensitive to being taken out/put back in and you say you did that on that wheel? They only have to become a nanometre out of postion to play up.
I'd take the hub and sensor off, clean up the reluctor ring, ensure the tip of the sensor is clean, put it all back together, making really sure the sensor is seated properly, (some suggest a light tap with a rubber hammer) connect it all up then get then clear the code.

As for trying to read the current or voltage generated, I'd say you would be wasting your time trying to do that. I don't think a domestic meter reading AC would be sensitive enough, but I could be wrong though. But a meter isn't a computer and the computer measures it and does other stuff with it to compare it to all the others before putting the 3 amigos on. @sierrafery knows much more about all this than me with my rickety knowledge of modern electrickery in cars. And don't forget you have to have the wheel turning at 10 mph or faster, so you'd need to do it driving along. Actually, you'd need two meters one for each front wheel to compare them, and even then the readings would go up and down like a yo-yo as you speed up, slow down and turn corners.
(Please be gentle with me Sierra!)
The computer knows how different one wheel's generated current can be from the other before it knows it has a faulty sensor. There will be differences, as when the front wheels go round a bend the inner wheel turns less than the outer wheel so it's reluctor ring will generate less current, but it knows the parameters and will not react to normal differences. If there is nothing wrong with the sensor. But if it can see that one wheel is generating far more current than the other then it knows that wheel is spinning so it applies the brake to that wheel to bring it down to within range. This is ABS, But if one wheel constantly generates less current than the other on the other end of the axle then it knows there is a fault and puts up the three amigos. The fault can be generated either through a wiring fault, or a faulty sensor, i.e. it is fubar for some reason, or the reluctor ring is turning too far away from the sensor thus producing current but not enough i.e. the sensor has not been seated properly, or it is intermittently creating either too much or not enough current, caused by a worn wheel bearing bringing the reluctor ring alternately too far away from, or too close to, the sensor.
I think your problem is the middle one, i.e. the sensor is not near enough to the reluctor ring, "low sensor output" would suggest exactly that. So you may get away with just loosening the securing bolt and tapping it into place with a hammer.
So I really do suggest you follow the advice up top and try to make sure the sensor is as far away from the reluctor ring as it is supposed to be. Others have said that it is possible to buy bearings with the wrong number of indentations in the reluctor ring. but if you bought all hubs from a reputable place, this shouldn't be a problem.

Feel for you buddy, this was me a while back. (Same time last year). In my case the garage's reader told me the wrong wheel so, just to be sure, disconnect the sensor, clear the codes and see what comes back, if it tells you more than one is now wrong you know that the reader is up the spout, one very famous diagnostic does this apparently. This is what happened to me and I then replaced a perfectly good hub for no good reason and ended up replacing the hub on the opposite end of the axle.
Hope my explanation of the possible fault makes sense. Remember a reluctor ring and the magnet in the sensor are just the components of a mini generator, or in this case alternator.
Best of luck.

This may help you understand how the abs works a little easier

backinblack said:

This may help you understand how the abs works a little easier

Click to expand...

Apart from the whiteboard, the baseball cap and the american accent, what did this video show that I had not already shown in my post? ("Tone wheel" my left buttock!)

Pictures

backinblack said:

Pictures

Click to expand...

Pictures of a dick in a Ball cap with a white board pen he annoyingly bangs on his whiteboard from time to time? Seriously?!

He may be a bit of a dick but his description was informative. And I have better things to do than look for videos that meet your approval.
I posted it to add to your already comprehensive description as I find pictures often help.

hey @backinblack don't pay any attention to me, i'm pished at the moment!

Drunk in charge of a keyboard, very dangerous

And as Churchill once said to Lady Astor, after she said "Winston, you are drunk!" "Yes, and you are ugly, but in the morning I will be sober!"

He also said lots of other stuff much of which wa hilarious and memorable. Will keep it till later!

thanks fellas
Appreciate you taking the time vid is a great summary and adds some measures which is good

I understand the way it works and feel I have a pretty good grasp of the advice on this site its just conflicting

Don't know why the gap could be too large (they are not touching- I did that test)
They are going into clean mating surface still shiny as hubs only 12 months old Ive taken out o ring and tapped them gently
I am fitting new "standard' sensor in to new "standard" hubs question ? are the after market choices really that poor to screw this up? if so they are not fit for purpose ? the feel of this site is don't by from the Stealers" perhaps we should list suppliers/ hubs that don't work ?
(local garage quoted £140 for new sensor from LR so can understand why you can't do this very often on a car worth £2000)
I bought from JGS 4x4 as some members here said they were pretty good so a bit disappointed if this is the case
The vid goes on the side of JGS and says rings must be clean and dry - again counter to the grease recommendations in some places on this site
regarding the tester fault codes

It seems to work pretty well I know its a cheap one but The fault always comes up same code on same hub the left front done this with 3 different sensors all now tried with no rubber ring
I have also used it to identify and fix the shuttle valve issue with mod option b

Video says test speed about 5 mph and Somewhere here it says revolve the wheel at 1 rev per second to test for the voltage and that's also about 5.5 miles per hour ? so that should be ok ?

I'll clean the bastard and then re test again both voltage spinning and clear faults and do a drive test
I'll also look at the other front hub for cleanliness/ similarity etc

Just occurred that I changed cv joint on RH front but not LH front so maybe there's some grease leaking ?

If ring didn't come with grease then it must be leaking from somewhere else - Its blue or green very bright looks like new ???
Now away for a couple of weeks (sods law) but will get on it again when I return
Appreciate your help and concern it would be good to get definitive clear advice on these in one place ?
Will let you know how it goes


Tim