300 abs light on.

This site contains affiliate links for which LandyZone may be compensated if you make a purchase.

sam

New Member
Posts
46
The abs light on my 300 tdi has come on after it was not used for about a week. I have checked all the wheel sensors and they all seem fine. checked all fuses and connectors I can find. Can anybody tell me were the fault code reading connection is and if there is any way to read the codes.

THANKS

SAM
 
Have cured loads of faults on trucks just by removing the wheel sensors, cleaning and refitting them, the vehicle then has to be driven, usually only above 5km/h or so, to clear the fault. Don't know how easy this is to do on yours but might be worth a try.
 
mines always on untill i drive about 10 FT ?? is this ment to be ?

i just assumed it was because its done it since i got it , start it up ABS light isn on , then when i drive a certain distance it will go off ? hhmmmm

someone shed some light plz
 
Hi the abs light will stay on until vehicle is rolling goes out when all wheels have done a couple of revolutions,the connector to read the codes is either under the dash near fuse box for pre 95 discos or just by the clutch pedal on 95 and over you cant read codes without t4 or some other computor hope this helps tiga
 
hi got the same prob with my 300tdi es went in hols for a week and on return abs light on also get a judder every now and then on the brake peddle and all i've been told is might be a sensor?
 
It's only a black art when it gets into the ECM and the silicon chip takes over. Basically an exciter ring on the hub will generate a current in the wheel sensor as it turns, the faster it turns the greater the current and this information is sent to the ECM. When you press the brake the ECM will sense the deceleration of all the wheels and will work out if one is locking, if it is, it will first maintain the same braking force to that wheel, even if you press the pedal harder, and if it still senses the wheel locking it will ease the braking pressure to that wheel. It was called cadence braking years ago! That is how a modern truck system works even with EBS (Electronic Braking System) which does get even more of a black art. Be interested to know how the system on a Disco operates in comparison although i suspect the principle is the same
 
thanks for all the reply's. been told today how to test wheel sensors. using a multimeter disconnect sensor and connect multimeter spin wheel you should read about 1.5 volts I think he said ac but if that fails try dc. Hope this may help others will let you know if it works.
 
Mine's the same, took mine to an ABS specialist who told me that all I had to do was hammer the sensor withe a blunt instrument back into place! Did not try it myself, but did watch him do what he said. I have however, found some info on the web that gives you the info on which component is causing the problem. Easy to do but not had time myself to try it. Here is the info, also covers Range Rover, if after you have read this and your still unsure, please, please, please do not try it, get some expert advice.

ABS Diagnostics

But there's an easy DIY way to read and reset these diagnostic codes. And you don't need a testbook computer - all you need is a bit of wire, or a paperclip!

There is nothing new in this document. All I have done is gathered together various other Internet documents, and added some notes on where the various connectors are on my Discovery. Many of the internet document relate to US-spec vehicles, where the components are located elsewhere.

My Disco is a UK-spec 1995 300 TDi XS.

The ABS ECU itself is a standard Bosch/Wabco part. If you do some googling, you'll find that the same techniques and codes apply to many other vehicles that use this unit.

First of all, we need to find the ABS warning light relay. On mine, it's in the passenger footwell, under the glove compartment. Lever out the 3 press-in studs, and the trim panel can drop. There are half a dozen relays in there. The one we're looking for is (on mine!) nearest to you, but in the second row, "behind" some others. Difficult to explain, but obvious when you get in there. The relay bases slide onto brackets, push them about an inch "away from the wires" and they'll come free.

The one we're looking for has a green base, and has 2 black wires, 1 black/green wire and 1 brown/red wire.

Disconnect this relay - pull it out of the socket.

Now we need to find the ABS diagnostic connector. This is where I struggled. All of the internet info says it's a blue connector under a seat, but that's just on US-spec vehicles. Rave says it's a 5-pin connector near the fuse box. But I couldn’t find that either. I believe that earlier (pre-95) models used this, but later ones moved it to the main diagnostic connector. This is a 16-pin socket, located under the steering wheel, just above the clutch. You don't need to remove any trim panels to get to it - although you may want to pop out the panel it's mounted on - it's not immediately clear how the pins are numbered, so look at the colours of the wires.

The 2 pins we're interested in are pin4 (black) - ground, and pin15 (red/green) which goes to the ABS unit. If the internet sources are to be believed, the abs diagnostic wire may be black/pink on some models, and on the 5-pin connector we're interested in pins 2 and 5. But this has not been verified.

You need some way of bridging the 2 pins. A paper clip or a piece of solid-core wire is ideal.

Now, we're ready to go.

Make sure the relay is disconnected. Turn on the ignition. The ABS warning light should come on, as usual.

Bridge the 2 pins on the diagnostic connector.

After 5 seconds, the ABS warning light should go out. It will then flash a pattern. From this, we can obtain the 2-digit fault code.

first of all there will be 2 slow flashes - one longer than the other, with a gap of about 2 seconds.

Then the interesting bit. The lamp will then flash, at about one flash per second. Count these flashes - that's your first digit.

Then a pause

Then it will flash out the second digit.

This sequence will then repeat indefinitely (start, digit 1, digit 2).

If you disconnect the link when the lights are flashing, it will clear the fault. Reconnecting it will show the next stored fault. If you have patience, you can read out and clear the entire contents of the ABS memory.

In my case, all of the stored fault codes were the same - 2 flashes, then 12 flashes. So you look up 2-12 in the table below, and find "air gap, right hand front wheel speed sensor." This ties in with my own experience - I know that re-seating that sensor will temporarily cure my fault!

Hope that someone finds this information useful.

Bruce.


The following table was obtained from

http://www.bba-reman.com/content.aspx?content=landrover_abs_ecu_fault_code_identification
 
just carried out checks as Disco es sent worked a treat thanks very much was the left front sensor. the diagnostic plug on my disc (early 300) was a small blue 5 pin plug next to fuses under steering wheel.
 
Sam, What year and/or chassis is you disco? Mine is 1995 MA14xxxxx, just wondering where to look for my ABS diagnostic connector.
Thanks.
 
Hello

I have just bought my Discovery, a 1995 Tdi ES auto. I'm really pleased with it so far, 1 week, but I do have the ABS warning light on. The car had stood for a while before I bought it last week. I took some advice from this thread and did the fault check with the paper clip and it has told me that I have a front right sensor problem, air lock or poor connection.

I've read about removing, cleaning and tapping these sensors but I am possibly the least mechanically minded person on this forum and need some advice on locating sensor etc etc.

Hope I can sort this as I love the car..

Thanks

Lee
 
Hi

In with the fuses, dropped panel beneath steering wheel and it was just there, blue connector and linked black with black/pink and away I went. Obviously after disconnecting the relay that Bruce mentioned in the previous threads, this was the one in the passenger footwell..

Hope that helps..

Lee
 
hi found a similar problem with my 300 disco.

under the glove box on the pass side where the diagnostics connector is, there is a little square box which connects with several pins, (i think its a relay switch) I pull it out tap it and put it back in and that cures it for a while, i think its a faulty switch, ive got to get one and swap it to be sure but maybe ive that a try
 
Hi all

I have this problem too,, I know this thread is old, but Im hopin someone will find it. My ABS light is on,,, (SURPRISE SURPRISE),, Ive done all the diagnostics as mentioned by DISCOVERY ES, and its telling me that its a problem with the nearside sensor (air gap) by flashing 2:14. I have had a multimeter on here and the reading seems ok,,, if not better than the offside.
the readings are at YouTube - Land rover ABS sensor readings and this was done with the multimeter set to 2000k ohm. I have also took the sensors out and checked the reading with, and without them touching something metal. I have swapped the sensors around, so that the offside sensor is now on the nearside, and the nearside on the offside. I took it round the block and it still comes up with code 2:14. So in my eyes its pointing to the relucter ring? Is it worth me getting a vernier gauge and measuring the teeth on both sides to check if the nearside teeth are worn?
Im also going to sit outside with a paperclip, for a few weeks to clear the fault memory and start again.

Does anyone have any other ideas of what could be the problem? or anything else for me to try?

Cheers all!!!!
 
thanks for all the reply's. been told today how to test wheel sensors. using a multimeter disconnect sensor and connect multimeter spin wheel you should read about 1.5 volts I think he said ac but if that fails try dc. Hope this may help others will let you know if it works.

How can you spin the wheel on a permanent 4 wheel drive? Am I missing something?:eek:
 
Back
Top