300 abs light on.

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Ok,,, Heres the latest.. Ive gone through all of the fault codes, and then unplugged the offside ABS connector, (to generate a fault code) and as expected, it gave me a 4-12 code. Tried the same again for the offside, and it gave me the 4-14 fault code. So i know the fault codes are working fine... With that out of the way,, I drove the car around the block again, and the ABS light was on all the way around, So came back and ran another diagnostic,, which is now telling me there are no faults!!! yet the ABS light stays on?
Ive checked the wiring with a multimeter from the ABS connections back to the ABS Control Unit, and all is fine there.. (if anyone wants to know which pins to plug into, gimmie a shout and ill get em on here)

So,, In Short

First, I was getting 2:14 fault code to which I cleaned the sensors and ended up swapping offside-nearside. and Ive had no more air gap readings since.

Then I have been getting 4:14 and 4:12 readings,, which relate to bad wiring,, which has been checked and is ok. (Although these were most probably generated while I was checking the wiring and creating faults)

Now im getting no fault codes at all,, but the ABS light remains on!

Ive swapped the relay and this made no difference, so the relay seems to be working ok.

Does anyone else know what maybe causing this problem?
 
DONE IT!!!!

Turns out it was 2 problems,,, Firstly was the air gap problem which was resolved by taking out the sensors and cleaning them (In my case swapping em to work out where the prob was) then it turns out the second fault WAS the relay. I just forgot to drive it after I swapped em round!!!

Cheers for you help everyone!!!! lol
 
Hi

Does anyone know what the correct resistance readings through the front and rear sensors is?

Also does anyone know how to take out the rear sensors without damaging them?
 
When in stationery position the resistance reads 9/38 - 9/40 except for one rear which only reads 48

Do you get the same sort of readings?
Thanks
 
D.A.W said:
When in stationery position the resistance reads 9/38 - 9/40 except for one rear which only reads 48

Do you get the same sort of readings?
Thanks
Click to expand...

Not sure,, I cant remember,, lol,,, and I think it depends on what your multimeter is set to,,, But if my memory serves me correctly,, you dont get any reading until its moving.. You could always try connecting the multimeter up and taking the sensor out, then touching the brake disk with the sensor while watching the meter? This should mimic the action of the spline that travels underneath the sensor?
 
My 1995 300 tdi that I just purchased failed the MOT - amongst other things the ABS light was inoperative.

So last night I set about checking fuses etc. with my meter. Found no volts to the abs light relay so deduced bulb was gone!

Removed dash today and found bulb was absent! (Nice sales trick?) Put in the trailer indicator one as this seems a bit superfluous.

Anyway - bulb is now on all the time.

Cannot find the diagnostic connector.

Their does not seem to be an ODBC connector above the cluthc - so I am looking for a blue connector "floating around".

There is a connector floating around but wire colours do not match.

Can anyone give more help on connection location.

Model is 1995 300 tdi.

Cheers

Stuart
 
Hi Discovery ES Member,

My Disco 2000 TD5 has the 3 omegos lit on the dash. Will your proccess work on my car as well?
 
stuartm said:
....

Cannot find the diagnostic connector.

Their does not seem to be an ODBC connector above the cluthc - so I am looking for a blue connector "floating around".

...
Stuart
Click to expand...

Found the blue connector, as described by someone else it was floating around!

Disconnected warning light relay and shorted black/pink to black as instructed.

I got a 2:2 code! Can anyone diagnose this?

Stuart
 
Solved it.

The fault codes on the link earlier are not a complete set.

Different years have different models of wabco abs. The problem I think is that the early models do not use the standard connectors/codes that the EEC enforced on car manufacturers to stop them charging extortionate prices for fixing our engine/brake computers. As a result mechanics and auto electricions cannot read the codes as they don't have the specialist readers/connectors. I tried a mechanic with diagnostic equipment who in turn tried an auto-electrician. The auto electrician got as far as the 2-2 code but did not know what it was or what to do!

OK here's what i did for my disco 95. It has a blue diagnostic connector under the fuse box. The instructions already in this thread may work for other models - but personally I recommend downloading the correct wabco manual - see below.

Firstly identify the model of wabco abs -
http://www.blackbox-solutions.com/docs/MASC-LandRover.pdf
Or, even better, read it off the unit. On my disco I stuck my head under the passenger dash and checked it on the bottom of the unit.

Next download the manual from wabco - mine was a type c.

Meritor WABCO -- Products -- Hydraulic ABS

These are great and contain the fault codes.

OK - so I took out my warning light relay and shorted the black/pink to black on the diagnostic connector. The light flashed 2-2 which indicates the hydraulic pump staying on. It only flashed 2-2.

I then spent a long time with the wiring diagrams in the RAVE and my Haynes manual trying to fix this. The only cause I could see would be the relay sticking - which it wasn't. I checked all the relays and the earths.

THIS WAS A MISTAKE.

When I read the manual again it said that faults are either stored or active. To check if a fault is stored you must clear it and then retest.

Again - earlier instructions in this thread did not help clearing the fault.

The manual said -
"While the blink code is flashing, turn off blink code switch and ignition."​

I don't have a blink code switch so I removed the short AND put the relay back in before turning off the ignition. (NOT just remove short as per earlier posts).​

The manual then says -
"Turn the ignition back on. The ABS
indicator will display one long flash and
one short flash, then repeat the fault
code. This will happen once, then the
lamp will remain on until the ignition is
turned off. This indicates the fault​
has been cleared."

It didn't - it just came on as normal but I then started again (removing relay etc.) and got a 2-3!

So I gradually cleared the codes and none came back. After about 5 or 6 clearances I went out to get daughter from school. The abs light went out as we left the house and the abs worked - but seemed to come on too much. On the way I stopped, turned off ignition and turned back on again.​

The abs light stayed on.​

When I got to the school I quickly read the fault code 2-14 - one of the ones I'd cleared earlier, and cleared it. (I can read and clear a code in about 30 seconds by now).​

Again light stayed out but when I stopped, turned off ignition and restarted it came on again.​

Read code again 2-14 which is front left sensor reading wrong when over 30 rpm.​

This now made perfect sense as the fault would not re-occur until car was in motion.​

Took off front wheel, sprayed sensor with wd 40 and tapped with hammer and bar and it slid down a few mm.​

Cleared fault and this time it stayed cleared even after driving!​

Then cleared all the other faults one at a time - not an exiting job.​

Now when I turn my ignition on the light goes on, off briefly and then on until I've driven a while - exactly as it says in the book!​

Note - even if your light goes off - if it does not flick out during the ignition sequence it indicates there are faults stored in the memory.​

So - my advice -
1) Persevere,
2) Get the right manual!
3) Note and clear down all the codes and then see what re-occurs before doing anything. My investigations into the 2-2 code lead to lots of others as I removed relays, checked connections etc!​

Any questions - give me a shout!​
 
this was a really useful post for me.. I have now cleared my fault codes and found only 1 - 2-6 [FONT=Arial, Helvetica, sans-serif](BPP)Brake pedal position switch

not sure if this refers to the same switch that works the brake lights but as I had that replacd a while ago decided to see what happens.. certainly now the light is out while driving for the first time since i have owned the car and I get the little wink when I switch the ignition on..


thank you...

[/FONT]
stuartm said:
Solved it.

The fault codes on the link earlier are not a complete set.

Different years have different models of wabco abs. The problem I think is that the early models do not use the standard connectors/codes that the EEC enforced on car manufacturers to stop them charging extortionate prices for fixing our engine/brake computers. As a result mechanics and auto electricions cannot read the codes as they don't have the specialist readers/connectors. I tried a mechanic with diagnostic equipment who in turn tried an auto-electrician. The auto electrician got as far as the 2-2 code but did not know what it was or what to do!

OK here's what i did for my disco 95. It has a blue diagnostic connector under the fuse box. The instructions already in this thread may work for other models - but personally I recommend downloading the correct wabco manual - see below.

Firstly identify the model of wabco abs -
http://www.blackbox-solutions.com/docs/MASC-LandRover.pdf
Or, even better, read it off the unit. On my disco I stuck my head under the passenger dash and checked it on the bottom of the unit.

Next download the manual from wabco - mine was a type c.

Meritor WABCO -- Products -- Hydraulic ABS

These are great and contain the fault codes.

OK - so I took out my warning light relay and shorted the black/pink to black on the diagnostic connector. The light flashed 2-2 which indicates the hydraulic pump staying on. It only flashed 2-2.

I then spent a long time with the wiring diagrams in the RAVE and my Haynes manual trying to fix this. The only cause I could see would be the relay sticking - which it wasn't. I checked all the relays and the earths.

THIS WAS A MISTAKE.

When I read the manual again it said that faults are either stored or active. To check if a fault is stored you must clear it and then retest.

Again - earlier instructions in this thread did not help clearing the fault.

The manual said -
"While the blink code is flashing, turn off blink code switch and ignition."​

I don't have a blink code switch so I removed the short AND put the relay back in before turning off the ignition. (NOT just remove short as per earlier posts).​

The manual then says -
"Turn the ignition back on. The ABS
indicator will display one long flash and
one short flash, then repeat the fault
code. This will happen once, then the
lamp will remain on until the ignition is
turned off. This indicates the fault​
has been cleared."

It didn't - it just came on as normal but I then started again (removing relay etc.) and got a 2-3!

So I gradually cleared the codes and none came back. After about 5 or 6 clearances I went out to get daughter from school. The abs light went out as we left the house and the abs worked - but seemed to come on too much. On the way I stopped, turned off ignition and turned back on again.​

The abs light stayed on.​

When I got to the school I quickly read the fault code 2-14 - one of the ones I'd cleared earlier, and cleared it. (I can read and clear a code in about 30 seconds by now).​

Again light stayed out but when I stopped, turned off ignition and restarted it came on again.​

Read code again 2-14 which is front left sensor reading wrong when over 30 rpm.​

This now made perfect sense as the fault would not re-occur until car was in motion.​

Took off front wheel, sprayed sensor with wd 40 and tapped with hammer and bar and it slid down a few mm.​

Cleared fault and this time it stayed cleared even after driving!​

Then cleared all the other faults one at a time - not an exiting job.​

Now when I turn my ignition on the light goes on, off briefly and then on until I've driven a while - exactly as it says in the book!​

Note - even if your light goes off - if it does not flick out during the ignition sequence it indicates there are faults stored in the memory.​

So - my advice -
1) Persevere,
2) Get the right manual!
3) Note and clear down all the codes and then see what re-occurs before doing anything. My investigations into the 2-2 code lead to lots of others as I removed relays, checked connections etc!​

Any questions - give me a shout!​
Click to expand...
 
Thanks Bruce. This worked a treat on my 95 uk spec disco. I managed to read and clear the fault codes for the cost of a paper clip which I may re-use anyway!. There were 2 faults stored on mine, wheel sensor and brake pedal switch. I haven't replaced these yet but I followed your procedure and managed to get the abs light out 1 day in advance of the MOT which is good news coz i also had to replace the boot floor but that's another story.

A few comments which may be of use to others reading this; my abs warning light relay was green like you said and in the location that you said but the wire colouring was different. Nice one Land Rover.

My diagnostic connector was under the steering wheel by the fuse box but was a 5 pin connector. Mine has black/pink wiring for the abs but was not pins 2 and 5. I guess the point I'm making is that there seem to be at least several variations of wire colours and connectors but if you follow your procedure and apply some common sense, your paper clip trick works a treat.
 
v8 disco biscuit said:
There were 2 faults stored on mine, wheel sensor and brake pedal switch. I haven't replaced these yet ....
Click to expand...

If the abs light is staying out then you probably don't need to replace them!

If there has been a sensor fault the light will stay on permanently until the stored fault has cleared. I think this is because the sensors cannot be tested during start-up - they only work when the wheels are turning.

I don't know if the brake pedal switch works the same - but possibly as the start up test would not be able to push your pedal! This could have been a temporary fault or maybe that switch broke/was disconnected at some point.

I think from memory of the circuit diagram that the same switch operates your brake lights too - so if they're working then the swith is probably OK!

If the sensor fault re-appears it is probably indicative of a "large" air-gap - not a broken sensor.

Jack and remove the relevant wheel. On the front wheel the sensor is on top with a wire going into it. Don't know where it is on the back but it'll have a wire! Spray with WD40 or something to lubricate, have a cup of Tea while this soaks in and then gently "tap" the top. I used the socket extension bar on top and hit it very gently with a small hammer. The sensor then slid down a bit. The sensor fault should then stay away!

If the sensor rides up again it apparently indicates a bad wheel bearing - the off centre rotation of the wheel pushing the sensor up too much.

This would be picked up on your mot anyway.

If you really think the sensor itself has failed you can test it with an ohmmeter (if you have one) as described in the manual - link above. Basically you have to rotate the wheel whilst measuring the resistance. However, IMHO non moving electrical components - like these sensors - rarely fail.

Good luck with the MOT!

Stuart
 
Thankyou hundreds of pounds saved....

ABS light on...

1: removed ABS warning relay in passenger footwell, (green relay, green base, (one of two) identified by four wires Black, Black, Brown/pink, Black/grey.

2:Turn ignition to pos 2. (ABS light ON)

3: For ease of use, unclipped 16 pin diagnostics in Drivers well used PIN 4 Black & PIN15 Green/Red. (Also present, but NOT used was Black/pink on pin16)

4: Bridged Pin4 & Pin15 ABS Light off, on / off / on...

5: pulses two distinct number codes, removed link

6: It repeats code while it deletes it.

7: re-established link, four times...got four different code, three airgaps 2/12, 2/14 1/15 and a wiring fault which has not repeated itself...5/12

8: ABS Light has remained off TOP MARKS you have saved me a fortune...a second hand sensor was £150, a new LR dealer one £400!!! and i dont need any! Ps My sensor had a pin prick hole through the end of it put a spot of araldite has sealed it up and has not effected its operation! Hope this helps others and thanks to all of you.
 
Having re-read my previous mail...1/15 should read 2/15 and my DISCOVERY is a 96 P reg V8 3.9ltr Injection. ES which should help you match info to your own car.:eek:
 
Well, I have a 95 M reg 3.9 and I cannot find the diagnostic connector for the ABS.

The "Nearest" I found was a 5 pin (round pin) connector, but its white not blue and none of the colours match up with all the posts I read.......I cannot find a blue connector anywhere :(

Anyone any Ideas ?

Also cannot find ANY relay in pass foot well with these ----- Black, Black, Brown/pink, Black/grey colour codes.........
 
Dunno said:
Well, I have a 95 M reg 3.9 and I cannot find the diagnostic connector for the ABS.

The "Nearest" I found was a 5 pin (round pin) connector, but its white not blue and none of the colours match up with all the posts I read.......I cannot find a blue connector anywhere :(

Anyone any Ideas ?

Also cannot find ANY relay in pass foot well with these ----- Black, Black, Brown/pink, Black/grey colour codes.........
Click to expand...



Are you sure that you have abs??
 
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