Brakes, almost crashed....

[beagleONE]

Hi all, just running about today in my 1996 D1 with "wabco" ABS system.

Was slowing down coming into a busy intersection, but when I put my foot on the brake pedal it shuddered and made a rapid mechanical clunking sound. I also pretty well lost all braking capabilities, so I had to revert to using the worn out hand brake to slow me, which thankfully it did as I missed getting cleaned up by a semi by a couple of feet.
I pretty well **** my pants :thumbsdown:


Anyhow, I pulled over to check my fluids. And they were all good.
So I limped straight home to start googling. Apparently ABS issues are sort of common with D1's.

-Do the symptoms I have described suggest ABS failure?
-Is it safe to pull the under bonnet fuse to bypass the ABS?
-How much trouble is it to completely remove the ABS, as Im happy to not run ABS for the sake of reliability.

[Tank]

For safety's sake, if you know nothing of brake mechanics, take it to an expert, your life may depend on it being repaired properly, Regards Frank.

[beagleONE]

Tis the plan Tank, definitely dont want to mess around with the anchors.
Have the basic understanding of how to do a bleed etc, but have never tinkered with an ABS equipped car.

Seriously considering taking it to a brake mob, getting extended braided lines and removing the ABS.

In the meantime, will removing the under bonnet ABS fuse ensure this doesnt happen again? Or have the symptoms described elude to something else being the issue.

[steveG]

ABS sucks on the D1 in my experience.
Does your ABS warning light work, and if so, does it ever show a fault?
I used to occasionally get similar issues on my D1, but I also got the occasional ABS fault which was wheel sensor related.
Sometimes giving the wheel sensors a good push back into their carriers would sort it out for me.

Steve

[beagleONE]

Hi Steve,
I believe that the ABS light works on ignition start up (will have to double check). But havent noticed it when it has been displaying these symptoms.

Yeah, after todays experience (if it is ABS related) makes me want to simply bypass they system as the fault is more dangerous than not having ABS.

Where are the sensors located mate?
Do you have to rip the wheel off to get to them??


Thanks for your help mate!

[Epic_Dragon]

boy that is scary! hope you get to the bottom if it. ive had similar in my D2, its like it breaks traction (chunks missing in my tyres) then abs goes on, it throws my foot off the pedal and does this weird thing and doesnt stop as fast as it other wise would.

[beagleONE]

So went for a quick drive around the local industrial area and tried to lock up the wheels, and engage abs to see if I could get a similar feel on the pedal.

Got ABS to engage a little (only just, slight pedal vibration) but it was not making the same rapid mechanical clunking noise and maintained braking capabilities :confused:

Went to TRS, the bloke was under the pump, so only got a half interested answer. He said may be the brake proportion valve, said about $100 for them to inspect and see what was going on... But I think hes off the mark there, as the rapid mechanical clunking noise sounds to be coming from the footwell/front area.


Its not doing it consistently, which is making it hard to diagnose....

[steveG]

Hi Steve,
I believe that the ABS light works on ignition start up (will have to double check). But havent noticed it when it has been displaying these symptoms.

Yeah, after todays experience (if it is ABS related) makes me want to simply bypass they system as the fault is more dangerous than not having ABS.

Where are the sensors located mate?
Do you have to rip the wheel off to get to them??


Thanks for your help mate!

Front sensors are in the top of the swivels, and rear ones go in horizontally. They are on the end of the only thick electrical wire that runs to to each wheel.
Its definitely different to normal ABS operation, and I've even had it in car park at about 10kmh so its not related to severe braking.
Went to pull up behind a queue of stationary traffic and :eek::eek:

Steve

[beagleONE]

Its definitely different to normal ABS operation, and I've even had it in car park at about 10kmh so its not related to severe braking.
Went to pull up behind a queue of stationary traffic and :eek::eek:

Steve

Spot on mate, so far that is when Ive had it happen to me. Low speed, randomly, generally turning left....
Ive had no issues at high speed, yet :thumbsdown:

And just testing it out under serious pressure (80km/h+) it brakes fine.



I checked out the under bonnet fuses.
Its an average picture, but visually the fuse seems in tact.
But I did notice some 'burning' near one of the legs
https://www.aulro.com/afvb/images/imported/2014/01/314.jpg (http://s18.photobucket.com/user/sloride/media/fuse1.jpg.html)



To help determine if it is ABS related, or the prop valve like the bloke at TRS suggested. Is there any danger if I were to remove the two abs fuses from in the engine bay and see if it happens again (ie, and danger of driving for a prolonged time with out these fuses in place???).
https://www.aulro.com/afvb/images/imported/2014/01/315.jpg (http://s18.photobucket.com/user/sloride/media/fusebox.jpg.html)

I dont really want to spend money getting the wrong thing diagnosed.

EDIT - Have also checked on dash brake light. Highlights 'brake' when pump fuse is removed. So works. No ABS specific lights though?...
Have had a look at the thick electrical wires. Someone has definitely tinkered with them in the past. Different colored cable ties holding them in place...

[SouthOz]

Ive had the same thing happen to me twice. Both times it was just as I was coming to a stop from low speed. A quick off then on of the peddle and it was gone. Hasnt happened again but I am interested in finding what the cause was/is.

Dave

[Aussie Drifters]

I had the same problem with my D1 (1996) nearly crashing into parked cars in shopping centers.
I was in a part of Australia where there was no Land Rover support so I pulled the ABS fuse and never had another problem.
Obviously this bypassed the ABS system so I am not suggesting this as a long term solution but it did stop the low speed braking problem.
By the way the ABS light was continuously illuminated on the dash.
I think the problem will be one of the sensors on the front brakes.
I hope that is helpful

[beagleONE]

yeah, the overwhelming response i have received has been
'sounds like ABS sensor'


has anybody pulled out the sensor?
replace, or just a general clean/crc??

keen to get this soooorted.

[gazby]

You mentioned previously that you were considering removing ABS system, you need to check if your vehicle will technically be roadworthy if you have it removed or rendered unworkable.
I've heard of a Disco 1 owner who was defected off the road for converting his ABS Disco 1 to non-ABS, his brakes worked perfectly without the ABS, as in an original non-ABS Disco of the same model, but the extra pipes (disconnected) were picked up in an "over the pit inspection.
So, might be worth checking out where you are legally before taking the step.
I chose our '98 "S" model because it had no airbags and no ABS, I'd heard the ABS in particular could be troublesome.

[SLOWBOAT]

If you take it to a LR dealer or authorised workshop who has the program to read the system it will tell you which sensor is faulty or requires replacement or it may just need resetting. The diagnosis is not expensive appprox. $50 to $90 depending where you go but a new sensor is a bit more costly.

[steveG]

If you take it to a LR dealer or authorised workshop who has the program to read the system it will tell you which sensor is faulty or requires replacement or it may just need resetting. The diagnosis is not expensive appprox. $50 to $90 depending where you go but a new sensor is a bit more costly.

Question for someone with more knowledge than myself...
Are the D1 ABS codes logged, or is it only current faults that are visible?
If its the latter then unless you've got the ABS light on its likely a waste of time/money getting the codes read.

Steve

[beagleONE]

^^^interested to find this out please. dont wanna burn money i dont have.

[discomatt69]

the codes are logged so it is east to find the fault, most faults are air gap to big, you can fix that but gently tapping the sensors in a bit being carefull not to damage the wiring.
the rear sensors are drug money to replace about $650 because you get both sensors and wiring loom that plugs in above the diff centre.

mine has had the same issue on occassion and a quick lift off and reapply of the brake peddle will work.

if there are no faults logged the ABS light on the dash will blink once when the ignition is turn on, if a fault is logged it will come on and not blink, sometimes it will turn off when you drive off other times it will stay illuminated if there are numerous faults.

[steveG]

the codes are logged so it is east to find the fault, most faults are air gap to big, you can fix that but gently tapping the sensors in a bit being carefull not to damage the wiring.
the rear sensors are drug money to replace about $650 because you get both sensors and wiring loom that plugs in above the diff centre.

mine has had the same issue on occassion and a quick lift off and reapply of the brake peddle will work.

if there are no faults logged the ABS light on the dash will blink once when the ignition is turn on, if a fault is logged it will come on and not blink, sometimes it will turn off when you drive off other times it will stay illuminated if there are numerous faults.

So in the OP's case, since the ABS light isn't on - there's no codes to read?

Steve

[discomatt69]

if the ABS light doesn't blink once there will be a fault logged even if the light goes out once he drives, about 5 km/h and the light should go out.

very few D1's will have no fault logged, slight worp in discs will log a fault so will loose wheel bearings, in my experiance its not worth the grief to try and fix it just learn to live with it.

if I ever bought another D1 it would have no ABS or SRS

[460cixy]

Fault will be logged for sure so you will need to find some one that can plug it in and check the codes in saying that you will find a bunch of stored info write it all down and clear them and go for a drive and try and get it to play up then read them again and see what you find. Things you can check is wheel bearing play this can up set the wheel speed sensors. But at the end of the day if you just pull the fuse the brakes will work just fine but with out the abs so no big deal at the end of the day

[PerthPT]

Same issue here, a knocking and clanging sound coming from somewhere in front, no link to the speed or rate of braking.

I've been thinking and discussed with a mechanic mate that perhaps one of the brake units ABS is seizing up, i've never actually taken one apart but apparently according to him there's a unit which slides back and forth when hard braking is applied and the ABS engages.

Thoughts?

[clubagreenie]

That'll be the shuttle valves which control the fluid flow around the ABS block to the caliprs. Converting to non ABS is illegal. If it is valves seizing it's probably due to contamimation in the fluid, you might find a good flush out and new fluid (which would probably not be a bad idea as it's either never been done or not done frequently enough anyway) might solve the issue if thats the source. If it's particle contamination and it's scored a piston or bore then is a new block.

[10 Toes]

Yep, mine did that push back shudder clunking noise as well. I tried all the stop gap measures, but brakes are things we need most. Took it to a Land Rover Bank in Burwood Victoria and handed over $2400 for new ABS sensors, Lines and brakes. Better now. like new.

[beagleONE]

for those interested, yesterday i gently tapped down the abs sensors on the hub.

since the original post, i had notice that the issue became rather prominent when braking on corrugations in the sand or dirt.

too the car for a test run to see if i could get the issue to occur again, and it seems to have cleared up a bit on off road corrugations...



shall keep you posted as to how effective this has been ;)

[Scouse]

since the original post, i had notice that the issue became rather prominent when braking on corrugations in the sand or dirt.

D1 ABS has been scary on corrugated roads (sealed or unsealed) from day one. Sometimes they feel like they are accelerating rather than braking when you hit corrugations on a down hill.

[98discovery]

You might want to take the advice offered by others and take it to the people who have the gear to diagnose the exact problem.I had that sickening shuddering experience several years ago in my D1 and got the offending sensor diagnosed and changed and have had no issues since.It did cost me around $300 all up but whats the price on safety?. You can try potshot fixes like tapping sensors etc but ultimately if its like mine and a intermittent sensor fault not air gap you can only be guaranteed of one thing and that is it WILL fail again and it will obviously be when you are trying to stop.