On start up first thing in the morning the ABS light, the exclamation mark brake warning light and the central warning light come on and the warning 'bong' sounds on our 2.2TiD estate. All go out if re-started and haven't come on (yet!) while driving. Also doesn't happen when when SWMBO leaves work at the end of the day.
So, faulty ABS ring on hub, or sensor, or is it the servo pump going home and not pressurising fully when first started?
All I can say is get it on Tech-II to get a fault code and investigate from there. Doing all the investigation without the fault code could be a couple of hours work with no answer!
Thanks Q, of course this morning after my first post I go out to start the car for SWMBO and - no warning lights!
Does it need to be the full Saab Tech2 as my nearest Saab indy & dealer is a 100 mile round trip.
It should have logged a fault code so just because it isn't doing it now shouldn't mean you can't pull any information from it. As for needing full Tech-2 or not, I honestly don't know, I've had people show me many tools that are supposed to be as good as Tech-2 for pulling codes but every single time they've failed to read anything more than a £50 code reader manages. I'm not the one to ask really given that I have access to a Tech-2 from work and if I didn't have one then I'd be stuffed ;D
I can read all the system codes on mine with an Op Com reader :)
OK, since my last post on this topic in September 2011 the ABS light and associated 'bong' has happened again! Only once yesterday and has not re-occurred since. Before it happened there was a rubbing sound at low speed which started before the light came on. Now I have noticed for some time now that when releasing the handbrake the car rocks as if the handbrake is not releasing properly on one side. When the rubbing sound occurred I went round and felt all the wheels and the nearside rear was warmer than the other three which infers to me that the brake could be sticking on this wheel. Now I know I will get replies saying get it on Tech-2 but I live over 50 miles from the nearest Saab service dealer so I need some constructive guidance.
Could a sticking brake be fooling the on board diagnostics into thinking the the wheel is locking and therefore cause the light to come on?
Possible - what's the bearing like?
A sticking brake would easily make the system unhappy. Service the brakes anyway if you feel that there might be a problem but keep that isolated from the ABS problem for now as you could easily have 2 different faults. Once the brakes are sorted see how the ABS fault goes.
Quote from: chris aka zaphod on 05 May 2013, 09:46:21 AM
Possible - what's the bearing like?
There is no rubbing sound at higher speeds, the car has 140k on the clock and prior to last years MOT in June I had new rear discs, pads and handbrake shoes, return springs etc. What is the service life for a wheel bearing?
Quote from: Audax on 05 May 2013, 10:12:43 AM
A sticking brake would easily make the system unhappy. Service the brakes anyway if you feel that there might be a problem but keep that isolated from the ABS problem for now as you could easily have 2 different faults. Once the brakes are sorted see how the ABS fault goes.
Thanks Audax, it's strange that the light came on back in 2011 before the rear discs were replaced and has never re-appeared until now !
Quote from: collywobble on 05 May 2013, 10:37:29 AM
Quote from: chris aka zaphod on 05 May 2013, 09:46:21 AM
Possible - what's the bearing like?
There is no rubbing sound at higher speeds, the car has 140k on the clock and prior to last years MOT in June I had new rear discs, pads and handbrake shoes, return springs etc. What is the service life for a wheel bearing?
OK, so it is unlikely to be the bearing. It should have been picked up as an advisory, at least, if it were showing signs, at the last MoT.
I would go around and clean all sensors and rings, as a matter of course. Simplest solution first, and this will be preventative work, anyway.
Turned out to be the return springs attached to the levers that actuate the brake shoes - so at least a nice cheap fix....