ABS Warning Light

windysurferuk · Unread post by **windysurferuk** » 27 Oct 2005, 17:15

My ABS warning light came on last week for an hour then went back off.

It has now come on again

I have searched the forum and have the same symptoms as mentioned in a few otheer posts i.e brakes not working correctly when the light goes out or comes on whilst driving.

I have taken the wheels off to check the wiring and to look for anything obvious but couldn't see anything (apart from my missing handbrake cable!)

I have had a look in the BOL which says there should be a connector somewhere along thewheel sensor wiring but I can not see any connectors.Should there be some?

Also where do I check the resistance of each wheel sensor?
I took the connector of the ECU but didn't know if this was the place to check it.

The car is a R reg xantia 2.1 TD

cheers

dieseldes1 · Unread post by **dieseldes1** » 27 Oct 2005, 21:36

quick check!
ign. off disconnect ECU multiplug

resistance all 1000ohms
Front LH Pins 1 & 2
Front RH pins 19 & 20
Rear LH pins 5 & 6
Rear RH pins 22 & 23 Some models 21 & 23

Voltage AC 0.1V AC minimum while turning wheel
Front LH Pins 1 & 2
Front RH pins 19 & 20
Rear LH pins 5 & 6
Rear RH pins 22 & 23 Some models 21 & 23
if you have an oscillascope you can check for an AC waveform across the terminals while turning wheel

This is a very simple check and unfortunately does not cover all faults!!

It sounds as if a sensor is faulty but could be is probably a faulty connector maybe even dampness as it has been really wet the last couple of days (well here it has been!!).

Des

Unread post by **Peter.N.** » 27 Oct 2005, 21:38

The most likely problem is a bad connection on one of the sensor leads. There are connectors along the leads somewhere but I am afraid you need someone more knowledgable to tell you where. I know where they are on an XM but that doesnt help you much. I am sure someone will come along soon...

marco1 · Unread post by **marco1** » 27 Oct 2005, 21:38

hi had exactly the same prob 3 weeks ago was front o/s wheel dont bother with citroen they wont £90 for one a bit of wire and sender go to a scrap yard like i did £5...and niked another one ....and ecu!!!! trace it fom abs ecu ..i will try and find the link its so easy just need a multi meter and put it into pin holes ..sorry at mo cant remember numbers..iwill try for you ...job done

Unread post by **Peter.N.** » 27 Oct 2005, 21:39

There you are, what did I say!

windysurferuk · Unread post by **windysurferuk** » 29 Oct 2005, 10:36

i can't seem to find any connectors on the sensor wiring.It appears to be a single wire right back to the ecu.

Are all the sensors the same I.E will a front o/s be the same as a rear n/s

cheers

jeremy · Unread post by **jeremy** » 29 Oct 2005, 10:52

The sensors are not the same front and rear - have a look at the GSF site (shop and catalogue) and Eurocarparts - (same sort of thing) as I think the sensors are stocked by them.

Have a look at

http://www.frenchcarforum.co.uk/forum/v ... hp?t=16638

windysurferuk · Unread post by **windysurferuk** » 29 Oct 2005, 11:21

just disconnect ECU multiplug but don't seem to have any pins in the following places or am I checking the wrong end

Front LH Pins 1 & 2
Front RH pins 19 & 20
Rear LH pins 5 & 6
Rear RH pins 22 & 23 Some models 21 & 23

Heres what I'm looking at. Pin one is marked in the bottom left hand corner but there is nothing at pin 2?

jeremy · Unread post by **jeremy** » 29 Oct 2005, 11:59

I haven't got the necessary diagram BUT if you take the shell off you may find 4 screened leads - which will be the ends of the sensor cables.

windysurferuk · Unread post by **windysurferuk** » 29 Oct 2005, 12:22

just done that but there are 14 thin wires 7 green and 7 brown. Even if i managed to pair them up I still wouldn't know which when to which wheel.

My only real option is to go to the scrappy and buy a front sensor and a rear sensor and try each one in turn??

My problem with this is I can see a way to disconnect the wiring on the sensor.
The BOL says to follow the wiring back from the sensor until I find a connector but I followed mine until it disappeared into the engine bay and can’t see a connector!

Any more ideas

cheers

dieseldes1 · Unread post by **dieseldes1** » 29 Oct 2005, 22:57

I have tried to make sense of your photo of the multiplug along with the Autodata drawings and information, I will take mine off tomorrow and compare!

Des

dieseldes1 · Unread post by **dieseldes1** » 30 Oct 2005, 13:32

The plug is on the abs Modulator control box on the n/s in front of the LHM tank! The photo you have taken is for the engine ECU ......

I have taken photo of the ABS plug which I will post when I get a few minutes to download from the phone, after the family things this afternoon

Des

windysurferuk · Unread post by **windysurferuk** » 30 Oct 2005, 15:15

dieseldes1,
this is a picture of my plug from the ABS in front of the LHM tank!
You can see the LHM tank in the background

dieseldes1 · Unread post by **dieseldes1** » 30 Oct 2005, 22:16

Sorry yours is an earlier ABS, I put your year and engine size into Autodata and that was the plug they gave, I had to go back to 96 and got the connections

F
15-30 L/H
1 - 6 R/H

Rear

19-28 L/H
29-31 R/H

All 1080 Ohms

Spin the wheels with the meter on AC and you should get a reading.

pin 1, 14, 26, all one side

Just shows never trust a manual!!!

or check the info before typing.......
Des

windysurferuk · Unread post by **windysurferuk** » 31 Oct 2005, 17:21

cheers for your help dieseldes1

I'll check them out after tea.

Does Autodata show where the connector's are to allow the faulty sensor to be changed? I still can't seem to find any on my car!

thanks again