Autocheck Brake Warning confusion

[Fat Audi 80]

Hopefully one of you guys can reassure me that I have no major problems?

MY Autocheck comes up with a Brake warning (!) every so often, usually when the car has been standing. Red brake image and three beeps...

I have done the Bomb check and I can get over forty pedal depressions. I have checked all my fluid levels and can find no problem. Do I need to get my car checked over?

I am tempted to leave it until it does it if and when I am driving.

What do you think?

Thanks,

Steve

[jubjub]

Go to "home" , look under "Technical", under "Brakes and ABS". There, if you scroll down, you should find the subject "Aaaahhrrggg Bomb", you should find enough info there.....BTW does can anyone tell me how to post a link, ie, to a subject that has already been covered...... It will save me typing instructions of how to find a previous post...

[Lee]

Go to the thread that you want to link to. Highlight the url in the address bar and press Ctrl+C to copy to clipboard. Next go to the thread that you want to reply to and submit a reply. Type what you want and use Ctrl+V to paste the content of the clipboard in your reply. You can also use the the 'http://' button in the 'post reply' dialogue and pasting your link there.

Try it out!

[jubjub]

I'm lost

[Alistair C]

whilst we're back on this subject -

As I've already said mine does this ever now & again too.
Not too worried as everone elses car seems to do it too - but what I have noticed is this....

The hydraulic fluid cap has a tiny pointy thing in the middle which is part of the float rod dangling inside the bottle.

On Peters ('Avant S2' on the forum) car, this bounces right back up when you push it down when the cap is fully screwed down - but on mine, when you push it down....it stays down. (requiring removal of the cap and manually lifting).

This would imply to me a dodgy cap / float.

Can anyone else (who also has this warning) try it on theirs?

I know caps aren't expensive & it would be very nice if this was a simple fix.

Ta.

[Fat Audi 80]

Thanks everyone. I must admit I did do a search and read a lot of the posts in the brakes forum. I am farily confident my bomb is sound as it passes the test and I know a new one was fitted by the previous owner.

I will try as you suggested Alistar and check the sensors in the fluid bottles to make sure it is not a sticking float.

Sounds like I will just get used to it and wait to see if it gets any worse.

P.S. Does a fault code get stored for this and would it shed any light on the problem?

Cheers guys.

Steve.

[Stick Insect]

Steve,

Does this appear once you applied the brake?

What is the image? is it the brake shoes or a bulb?

If it is the bulb symbol it could be that your rear lights have water in and are causing a bulb failure to appear. see thread http://www.s2forum.com/forum/showthr...&threadid=1757

If it is the brake shoes then Please follow the brake threads.

Just my tuppence. ( Tuppence is a rude word in Stoke on Trent you know!)

David

[Michel]

I had the same problem.....usually every morning before I touched the brakes.

Did all the tests mentioned on the S2 Central.. all good, so I though no worries.

But on thinking about it it does store pressure for both power steering and brakes....so if for some reason you lose engine power then its allyou've got to get you stopped...

Its only 'cos my Golf threw a rod thro the block on the right hand lane of the M25 at 70mph (!) the day I got it bakc for a service that I get twitchy about that sort of thing.

[Fat Audi 80]

@ David, Its the Brake shoe logo type warning red symbol followed by three beeps. It only does it after it has been standing and I cannot remember it ever doing it during the day only after a night standing in the garage. It happens after I have applied the brake and never before the Check Brake light amber symbol you always get. Would this be a brake shoe/pad level wear warning. It does not mention this feature in the Audi manual!

Cheers again.

Steve.

[Stick Insect]

It may be a really uninforming error. It may relate to pad sensors, fluid level, bomb etc. ( I suppose a check of th manual might tell.)

OK Steve,

As I am the main technical contact for my car club i have to use lateral thinking many times.

There was mention further up the thread about the float in the fluid reservoir sinking. if the fluid is on the low side and you move the car just by sitting in it them the sensor may throw a fault.

I had a Montego as a company car and when the pads wore down the fluid level dropped, when the level dropped and I went round a roundabout the light sometimes came on.

Check fluid level, look at the brake pads for wear if you have been cleaning the car and polishing the car it can cause an error...

sorry seriously though acid brake cleaner can have a nasty effect on the pads and sensors.

Does the 3 boings indicate something can anyone say?

I feel 3 is normal.

D.

[Cobstar]

Haven't got my handbook here but I think the 3 bongs means a warning of a potentially serious fault and is accompanied by a red warning image - ie brake symbol. Scared the living daylights out of me the first time it happened - never had such an intelligent car and I thought I'd broken it.

Things like bulbs and windscreen washer get a yellow/amber image and I think only one bong.

Our cute little Seat diesel goes bong to tell you when the temperature drops below 4.5 degrees C and there is a risk of freezing. Ahh - how sweet.

[dan_b]

Have you checked your powersteering fluid level? You get the same "hydraulic fluid warning" alert for the PS system as the brake system, which is stupid.

Mine bongs at start up, but that's because I've got a leaky rack. When I top up the PS fluid, it goes away.

[Stick Insect]

I wonder if things go bong much in Holland?

D.

[Alistair C]

yes - the three bongs and the (!) symbol does indicate that the car is trying to tell you there is a serious issue.

However - if you look back through the brakes section you will see several posts all filled with people saying 'mine does that too'.

http://www.s2forum.com/forum/showthread.php?s=&threadid=1700

It seems like there is a common fault here which no-one seems to have identified yet. The common feeling though is that it is not as serious as the bongs indicate. Most people who have experienced it have tested their cars according to the S2central tests & have no indication that anything is seriously wrong.

Personally I want to stop it happenning at all - regardless of whether it is a genuine fault or not.

PS the car has no pad wear sensors - this is a hydraulic fluid warning (ie brake / PAS)


Anyone else checked their float???

[S2central.net]

Alistair,

The only way to know for sure is to test with proper hydraulic pressure gear and some funky adapters from VAG that fit onto hoses.

I have all the test info, but none of the expensive hydraulic test gear

I know several S2s that can pass the pedal pump test (when done immediately after shutdown from warm), but still have the occasional 'red alert' when left standing cold for a long time. This is because it takes the extended time and reduced temperature for the reservoir of pressure in the bomb to reduce to the level where a pressure alert is triggered.

With a healthy PAS pump there is no immediate concern (unless you get the red alert sufficiently often to worry you) as the system will quickly get back up to pressure when the engine is started, but you are on the margins of safe driving... Remember the bomb is only really needed in an emergency situation to give enough hydraulic servo assistance in the unlikely event of an engine stall during extremely hard braking.

TopTip - find a quiet wee hill somewhere safe, parkup on the handbrake, turn off the engine, empty the brake servo with the pedal pump test, then with the engine still off - release the handbrake and see how heavy the steering feels and how much leg effort is needed to work the brakes ! Be careful though and I'll bet you will be glad of the handbrake !!!

I always have to say this also - check the colour of your hydraulic fluid. If its red then replace it with proper GREEN G2000 fluid ASAP - your bomb, servo, PAS pump and rack might already be damaged forever....

Cheers,

Paul