Technical The curious case of the Orange ABS light

[Brim987]

Hi All,

Well, after the joy of fixing the red injector warning light by giving the Marea
a good thrash up a hill... we now have the orange ABS light.

I've seen a few really worrying threads on here about ABS lights but none quite the same as what I'm seeing..

Sometimes the red exclamation light is also on, sometimes (usually) not.
When the orange ABS light wasn't on, then the exclamation light went on and off perfectly with the handbrake so I doubt it's a handbrake switch issue.
(I'm not sure what all the possible causes are of this light being on...)

I put some brake fluid in, fiddled with the diagnostic lead by the fuse box
(just looking for it) and the orange light went away for a day, but now it's back. (Obvious thought is a leak but the levels look fine), maybe more like coincidence.

Here's the curious bit, when the orange light is on, during a week's driving I've noticed - maybe 5 times - what I can only describe as a tickle on light braking, low speed, dry road, no reason at all for the ABS to be coming on but I don't know what else it could be.

I have experienced the ABS kicking in on other cars when I have had reason to mash the brakes, but it's nothing like that sort of heavy pulse, it almost feels like dirt on the disc, it's that light. I'm sure I'm not imagining it.

The other thing I should mention is I know the front discs are pretty shot, I was planning to replace them if it survives the mot.

I can believe the worn discs/pads might cause the warning light, but the tickle?

Any thoughts appreciated, my boy adores this car, I don't want this to be an MOT fail and car killer issue.

Steve
P.S
Previously, Multiecuscan was recommended to me - I didn't get it because the red injector light went away and I wasn't sure what cable I needed. I read in other threads that even the garages weren't able to diagnose issues accurately which worries me.

 

[jockmr2]

abs sensors on wheel hubs, worth a look, even check the wiring on them, an open wire somewhere might be causing your erratic lights going on, abs pump could be another part failing, without diagnostics it's just going to be a search mission.

 

[Neverth]

Also depending on the system the ALB might be stuck if you don't have the mechanical valve in the rear axle and the ABS unit does the load distribution, possibly giving wrong pressure to some wheel. Known good way to get it working is to take the car to some slippery area and brake it hard/in a turn/while in gear on throttle so the abs valves actuate and unstuck themselves and circulate the fluid inside the unit.

Also if you got the non bosch abs, you might have failing pump relay, but the symptoms do not sound like it.


The handbrake light is also brake fluid level warning.

 

[varesecrazy]

Also depending on the system the ALB might be stuck


The handbrake light is also brake fluid level warning.

Whats the A L B ..?

Yes the brake fluid reservoir probably still has a 'float' indicating the fluid level.. using the 'Brake System' warning light - info for Brim987

 

[Brim987]

RE: The handbrake light is also brake fluid level warning.

That makes sense, the red exclamation light hasn't been on since I topped it up.

I'll go to a local farm next week and see if I can provoke the ABS in a field!

Otherwise, it's feeling like pay a garage to change everything until something works.
Ouch.

The next question might be what's the easiest way to get to the bulb...

Steve

 

[Neverth]

Whats the A L B ..?

...

Automatic load balancing. You load your rear full of stuff, the suspension compresses a bit and you got more traction in the rear. On mechanical ones you got spring that pulls on the proportional valve from the anti-roll bar to apply more pressure to the rear brakes. On ABS controlled the valves inside the unit do the pressure regulation.

 

[varesecrazy]

Nobody local to you on the forums MES register ?

 

[Brim987]

RE: Nobody local to you on the forums MES register ?

Sorry, what's that?

Steve

 

[Brim987]

Quick update, I'm now convinced that the ABS is kicking in about half the times I touch the brake. It's a weird tickle through the pedal.

It's booked in for next week, I suspect it'll be a case of change the front sensors, and then book it back in (two week wait) to change the rear sensors if not fixed.

Then... yikes... I just hope that's all it is.

Steve

 

[Brim987]

Just replying to myself here.

The brakes are just horrible (basically hardly work at all) after starting the car and driving for about a minute.

Then the dash lights come on (meaning the ABS is turned off) and the brakes work again.

I manged to get a fault code for left front wheel speed sensor, the garage changed that and the lights went out.. for a day or two, but now back to where we started.

It seems the brakes are horrible when setting off because the computer thinks the front left wheel is skidding.

The sensor change fixed it briefly, all I can think of is get them to fit it again on mot day and hope it works just long enough...

Any thoughts appreciated though..
?

Steve
P.S
One other thing my son noticed when starting off there's a curious whirring noise (sounds like passenger side, front of the car) which starts/stops 3 times and then gives up.