warning beep on uneven bumps

[ralphb]

My warning beep goes off every time I go over an uneven bump in the road (also my driveway - its driving me mad!) It has to be a significant bump, ie not just an uneven road surface, and it happens even if I approach it at snails pace. Road humps, where both wheels go over at the same angle of approach don't set it off at all. There doesn't seem to be any problem with the car otherwise - still firm roadholding, no apparent problem (that I can tell) with the shocks, although I haven't had them tested.

Any ideas?

[alastairg]

What actual warning shows on autocheck ?
If it is the red (!) then check brake and hydraulic fluid levels which if around low limit may trigger on a bump.

[ralphb]

Thanks Alistair - its the whole warning christmas tree. Brake fluid OK, but I'm clueless here - I didn't know there was a separate hydraulic fluid!

[alastairg]

Small green container in front, below screenwash. Just this happened on my previous S2

[SimonS4MTM]

Perhaps its telling you to keep away from bumps

[GlynRS2]

Could be a loose sensor, connector or relay I guess.
But I would check fluid levels first as Alistair suggests as this is much easier to do.
Good luck

[ralphb]

Thanks. I checked the warning type - its the exclamation mark in a circle - so not very helpful.

Simon - I couldn't keep away from bumps - I get huge satisfaction by speeding up when approaching speed bumps - its one of the joys of the RS2!

[GlynRS2]

That is a hydraulic system warning light. Surprised you have never seen that before. It is the one that goes when the brake bomb goes etc.
See here for a full explanation:
http://www.s2central.net/brakes_02.html#bomb
However, as your warning only goes off over bumps I would check the fluid level in the hydraulic/PAS fluid resevoir first. Slightly overfilling this frequently sorts the problem.

[hiltron]

Had same problem. Overfill fixes it.

[ralphb]

Thanks, I'll try overfilling it tomorrow. Just got the car back today after a week after having the turbine house replaced (after waiting 6 months for a part) (I'll photograph the one that's come off for another thread). Unfortunately I didn't check back here in time to tell the mechanic to try this - he tried to figure it out to no avail. He said he couldn't find the sensor plug for the brake sphere as he said the problem seemed to that there didn't appear to be one as he would expect ...I was about to ask that question but maybe its redundant..

[ralphb]

I've just read the link given by Glyn above...I went to test the brake pedal and it feels pretty dead immediately, let alone after 10 pumps! They certainly feel exactly the same whether the engine is running or off, and no different either way after constant pumping, even after 50-odd. The warning light does sometimes come on after a while though - as it has tended to do under emergency-type braking.

I still need to try overfilling the hydraulic fluid, but from my amateur diagnostics tonight it seems to be a case of a completely knackered "bomb"...

The brakes feel as if they are working fine whilst driving normally though, and having had the car for 2 years including 2 or 3 track sessions, I've never felt that the brakes were under-perfoming - nor has anyone else. So what's the big deal..? When and why is it absolutely vital to change the bomb and why isn't it patently obvious to my mechanic

[mastermind]

I have the same Dam Problem on my (R)S2coupe, Tested the Bomb and the brake pedal goes rock solid after 50pumps.
I will try overfilling. It also shows that the roads here in CT are getting more bumpy.
My RS2avant did this but that was solved by a slight top up of the fluid.

[Greg_S]

also worth checking the contact on the reservoir. and also make sure that you disconnect the connctor befor lifting the cap off otherwise the float gets bent and cant stick triggering the warning light.

Greg

[ralphb]

Its definately not remedied by overfilling, and to prove the point, I disconnected the sensor from the cap completely and it still triggered the warning light - so the light is being triggered by a different sensor - so where is this as its not apparent from a visual inspection of the bomb? I understand that my completely knackered bomb is something that I could live with(as long as I have a good right foot and strong arms to muscle the brakes and steering in the event that I stall) - as long as I could disconnect the mysterious absent sensor! ...this is a bit of a technicality now as I've decided to replace the bomb (about GBP350 part only) anyway.

[AAH!]

Worth a try:

http://www.audifans.net/modules.php...iewtopic&t=7324