Intermittent ABS Fault?

[phatrex]

My ABS light is coming on intermittently and I'm wondering if any of you guys can help? (It's a Version 2 by the way).

When you start the car, the ABS light shows (and I'm assuming does all it's checks), then goes out, so I assume it thinks all is okay. Randomly though, the ABS light will come back on, and stay on. Sometimes it doesn't. The rotors have been off today and the brake system has had a good clean up. There's no issues with the hubs etc and the ABS itself works fine so I'm wondering if this is electrical.

Is it a dodgy sensor or a dodgy wire or something? And if so, what can I do about it? To make things harder I'm running a Link and can't retrieve the fault codes from the ECU.

Thanks for the idea of disconnecting the ABS light - but no thanks!! ;D

[Guest]

i belave there is a way to get cheak codes off some ABS units in regaurds to the abs its self.

thats as much help as i can be though, sorry, good luck!

-smurff

[Guest boostin]

The Link has nothing to do with the ABS.

The ABS ECU is under the drivers seat under the carpet. Next time the light comes on while driving, pull over but don't shut off the ignition. Roll the drivers seat right forward and lift the small flap of carpet. There will be a flashing red LED. You may need a mirror to see it. Count the flashes and write it down. Google it when you get home.

This only works for Gen 1 Legacy's and V1 & V2 Impreza's.

[Guest]

^^^

there u go, thought there was something like that,

same idea with some legacys, but its located in the centre console, infront of the shifter.

-smurff

[Guest boostin]

 smurff said:

^^^

there u go, thought there was something like that,

same idea with some legacys, but its located in the centre console, infront of the shifter.

-smurff

Nope, thats the airbag ECU.

[phatrex]

Sweet, thanks very much!!

....and here's me thinking that only my Amp was under the driver's seat!! :

Will post the result up in case someone else has the misfortune.

[Guest]

 boostin']

[quote name='smurff said:

^^^

there u go, thought there was something like that,

same idea with some legacys, but its located in the centre console, infront of the shifter.

-smurff

/quote]

Nope, thats the airbag ECU.

thats right, got my wires crossed :P

cheers for the fix

-smurff

[phatrex]

 boostin said:

The ABS ECU is under the drivers seat under the carpet. Next time the light comes on while driving, pull over but don't shut off the ignition. Roll the drivers seat right forward and lift the small flap of carpet. There will be a flashing red LED. You may need a mirror to see it. Count the flashes and write it down. Google it when you get home.

This only works for Gen 1 Legacy's and V1 & V2 Impreza's.

Next stupid question - please can you tell me where the LED is on the box?!? :

ABS Light on, ignition running, seat forward (carpet flap lifted - then carpet appropriately munted in frustration so I can see all of the box!) and all I see is a sealed ECU unit!!

Many thanks in advance boostin!!

[Guest boostin]

The LED is inside it. There should be a small window to see it through. As I say, you normally need a mirror though.

[phatrex]

OK, thanks for getting back to me - but I seem to have a sealed box with no window. And I've cut the carpet to have a good look at the ECU! Even took the carpet out around the drivers door frame and still can't see an LED.

Oh well, might be seat out, carpet back, and lid off ECU box next then....

There's been a few mongrel things with my car with it being virtually the last V2. What type of connector should I look for under the dash for a V3 set up!! (Serious, it won't be the only thing V3 on it!!). Thanks again boostin!

[phatrex]

It looks as though my 1996 V2 may have the newer version ABS system. Using the great link above (Checking ABS Codes - BG5) I THINK I may have a Diagnostic Link Connector No 24 under the dash.

Does this connector sound right for V3/4 Impreza's?

[Guest boostin]

It could well do. I thought V2's were the same as V1's with the LED, but obviously not.

When you find that connector, post a pic up.

[phatrex]

It looks like the ABS ECU version with the flashing LED may have only been produced until 1995. I believe there were 2 different MY's of V2, Sept 94 - August 95, and Sept 95 - August 96. It's possible that the second batch had the new ABS? Don't know, just guessing. Hope to finish this saga off soon (then comes the repairs of course!).

[Guest itsgotgo]

if the light comes on at a random time when driving and stays on,it could be the clock spring behind the steering wheel.

over time they can become faulty.replacement one i brought was $160 plus labour for fitting.

if it is the clock spring it will become progressively worse given time.

[phatrex]

I finally have an answer to this (and a bit of ruined carpet under the drivers seat!).

My 1996 Version 2 definitely has the Diagnostic Link Connector No 24 under the dash. When I earth it to the steering column, it gives me the following codes on the ABS light (with what I believe the codes actually mean):-

11 - Start Code

27 - Abnormal ABS Sensor, open circuit or voltage too high; rear left ABS sensor

28 - Abnormal ABS Sensor signal, rear left ABS sensor

25 - Abnormal ABS Sensor, open circuit or voltage too high; rear right ABS sensor

Now I'll take it to someone who can help me fix them!! Any guidence on the above problems will be gratefully received.

[DRFVDR]

I would check the left rear sensor wiring

if it does look ok then replace sensor

[phatrex]

 CUDDAS said:

Just a thought, in your sig your @ a track day. have you removed your rear seats & dislodged one of the abs plugs that run thru the body or a wire, while it's in that area?? just a thought

Mmm, that's an interesting thought, thanks. I upgraded to a V8 interior a couple of years ago and haven't changed it since so that shouldn't be it as it didn't come out for Megameet 09(which is the signature photo). However, I did bring passengers and quite a bit of gear back from the track day that I didn't take up...... The fault seems to have been intermittent since then... Will check that out, thanks.

I can actually make the light come on at will now. Right hand down, power on (heavier than norma!l), ABS light comes on. If I nanna around (which is normal!! ), the light doesn't come on.