Brake warning light

[Dippy]

This morning I had a short journey to drop off my girls at the nursery. When I got back in the car and started it up, the brake warning light came on for a few seconds (with the audible alarm) but then it went out. I tentatively made my way to work and the brakes seem fine (no spongy pedal). I checked the fluid level and that's fine. I then turned the ignition off and on a few times (and again just now about 2 hours later) and the warning has not reappeared.

The only thing I haven't done is checked with VAG-COM as my laptop is temporarily unavailable.

So whilst I'm inclined to be safe and have it checked by a dealer, I am loath to do so as I'm sure it'll be a waste of time.

I thinking that maybe it's just a glitch due to the cold weather. Any ideas?

[wazza]

This thread may help [img]images/graemlins/thumbs.gif[/img]

[peterb]

Strange! As I started my car just after 11 last night (having enjoyed the Choir Christmas Dinner), the warning buzzer sounded and a symbol appeared on the DIS, but I wasn't quick enough to notice which symbol it was. It could well be that this was also a brake warning. I have dumped the DTC codes this morning (because of another problem - see separate post) but nothing showed up.

[SimonS4MTM]

Oh no, not another ABS ECU

[martian]

Strange! the warning buzzer sounded and a symbol appeared on the DIS,

I get this ALL the time- I had the car back at Audi twice for this- no diagnosis was made and no rectification. I have found that if I start the engine and wait minimum of 5 seconds before putting my foot on the brake, it does not happen. If I'm too quick with depressing the brake it happens every time.

[Dippy]

Thanks,

Sounds like I shouldn't worry too much unless it happens again. I'll check the diagnostics with VAG-COM when I get my laptop back.

I do hope that there's no problem with the ABS...

[martian]

I do hope that there's no problem with the ABS...

I hope I did'nt mislead you - was it the yellow ABS or red BRAKE warning?
My problem is with the RED brake warning NOT the ABS

[ChrisB]

Oddly enough, I had a red brake warning recently, but only on cold mornings. It was simply a low brake fluid level.

Not sure how it got so low between services though - can't find any leaks.

[Carps]

Perhaps you have been braking 'enthusiastically' and this is merely an indicator that your pads are worn [img]images/graemlins/thumbs.gif[/img]

[Hopsta]

I've had this too earlier in the year, would come on when i was braking a low speeds and was very intermittent. The stealer replaced all the brake light bulbs in the end, even though they all appeared to be working ok.

Graham

[peterb]

Strange! the warning buzzer sounded and a symbol appeared on the DIS,

I get this ALL the time- I had the car back at Audi twice for this- no diagnosis was made and no rectification. I have found that if I start the engine and wait minimum of 5 seconds before putting my foot on the brake, it does not happen. If I'm too quick with depressing the brake it happens every time.

Of course, on starting the car, the brake lights and electrical circuitry is automatically tested. One of the tests is on the brake light switch. If the brake pedal is pressed during this diagnostic phase, then the system will report a fault (the buzzer sounds, and the brake symbol is displayed with a bulb symbol in the centre). This sounds exactly like what you are describing, Martian. Could it be that Dippy and I both, unwittingly, provoked the same symptoms within ten hours of each other? Perhaps the cold weather induces a tendency to press the brake pedal on starting the engine? I would also guess that releasing the brake pedal will immediately clear the fault - hence the symbol doesn't stay up long enough to identify it - perhaps the warning buzzer, subconciously, causes us to take our foot of the pedal.

[Dippy]

It was indeed the red brake warning light and not the yellow ABS light. It has not happened since and the brakes are fine (AmD changed them at my 40K service a few weeks ago).

I'll check Peter's theory about the brake pedal. Or maybe there was some recent cosmic activity over the Reading area...

[Dippy]

Hi Peter, I just checked start-up with my foot on the brake pedal. It did not cause the warning...

[Carps]

Enter the Twilight Zone...

OK, so I'm on my way to work this morning - happily poodling along in the early hours with no problems. I stop at a newsagent to buy a paper, get back in the car and turn the key to be greeted by beeping and a flashing brake warning light ! First time it's ever happened, and sounds like a dead similar scenario to Dippys' original story. The light went out, and when I turned off the ignition and turned it back on again there was no light.

I reckon it must be something to do with the cold. It'd be interesting to see how many other people experience this. I'll be plugging into VAG-COM tonight to see if there is any fault, but I suspect not. I'm also going to phone my dealer to see if they no of any such problem. Will post the outcome...

[Dippy]

This is strange. I never had this happen in the past 2 years, and neither did I see any previous reports here or on AS-net. Wierd.