initial comments point to battery also but fluid is also a factor .. i have finally gotten my car back at lunchtime having been away from it with work for hours and hours so was able to check fluid .. bit dissapointed it was serviced 2 weeks ago and they ignored that?
Either way i have fluid, battery and switch all on order!
Please Help: Brake Problem -(
We've all got different opinions
In my experience if the light comes on in the situation you've described it's due to lower battery power and the ABS module rather than low brake fluid. Brake fluid level is of course very easy to check and eliminate.
If you're doing the pedal switch too that will help, PM me your email and I can send you a pdf guide to do that.
how much is an ABS Module? - And can i test that to see which of the 2 is the problem rather than buy both?
PM on its way!
Fit the switch, if it doesn't help get the battery tested. If that's inconclusive replace it anyway and that should fix it.
Don't stress on the ABS module, I've *never* heard of one go on an A4 personally.
Parked facing the opposite way on the hill last night so i was facing the right way for this mornings journey and hey presto - no error?
So if it is fluid related - it makes sense as the angle i was parked at this time would of told the car it was nice and full .. the other way - it COULD think its empty i guess ..
Also was a bit warmer this morning and no frost ..
the sensor is on the bottom up down sideways the same
does it come on when you go round a corner ?
I can definatly tell you that the yellow brake warning light is the pads low and the red one is the brake fluid/ handbrake light. I hadn't stated my a6 for 3 weeks and the red brake warning,light came on , beeped, It had never done it b4, the battery on mine seemed to turn the engine over as normal. so i looked at the brake fluid res and the level was a bit down, topped up and gave the sensor wire a wiggle and it seemed to do the trick, has not come on since. I know a lot of guys have experienced this fault and its the battery , but in my case it seemed more fluid related.
The voltage drop when cold cranking has nothing to do with the abs its draw at the dash insert and in most cases the battery is perfectly serviceable
to check simply press the check function on the dash when cranking and the fluid level warning will come on
if the battery is in order and the fluid level is in order carry out the relay mod in the link to eliminate the spike
I have the original battery and the mod carried out two years ago with no further issue
If you think the battery is weak then test it and the cranking volt drop
Ok, fluid just turned up in post :D lol
Cap off and topped some up and the level hasn't moved?
Theres like a plastic filter/sieve thing in the cap and the fluid level is now sitting above this BUT the actual line on the tank hasn't moved?!
okay job for after lunch! lift it though yeah?
and it comes clean out? looks more like I'm going to snap/brake it tbh
I did post it up 2 years ago on vwaudiforum but people don't search forums for answers do they lol
Mainly 2.5 tdi b6 a4 cabs suffered the most and we used aluminium foil around the starter cable as we thought it was running to close the master cylinder in the plenum chamber
The quick check is to press the check button on the dash when the red light comes on
If it highlights fluid level then the mod is required unless you do have slow cranking
You see the battery will be under greater load from cold start so it doesn't mean its goosed its just this drop in voltage when cranking creates the problem although the driver rarely complains of slow cranking speed
X relief should by nature turn all un necessary consumers of for maximum cranking, so taking this circuit out briefly allow the signal to be interrupted and no more red brake warning
At the time warranty refused to pay for battery's as they passed the cold crank test when returned to factory and battery's are only covered by warranty if they are consequential or a proven history of good maintenance ie not been sat on a pitch etc
Most battery's prematurely age due to lack of maintenance and ironically that's due to sales pitches etc
When you next visit a dealer take a look in the showroom and you will see the cars are hooked up to chargers discreetly
clever info there bud mine defo was a dud battery in my case, original battery and the sells was all distorted and dry, new fitted and no more faults since
A4 TDI 130 SPORT..
now sold but still in the family, gone back in time to the cupra R again..