Dash Brake Warning Light with no Error Message / Code

[jonmckeown]

Hello,

Just recently, I started getting the BRAKE light on my dash at the beginning of my drive on my 2011 Q5 3.2 Premium Plus with 72,000 miles.

When I accelerate with some oomph (not just nursing the car along), the light will come on, beep three times and then go off when I let off on the pedal. The brake fluid is full. The pads are in great shape and have tons of life left on them. When I press the SET button, I don't get any messages. The ABS light has never come on. I don't get any error codes when I run my scanner. And after I drive for approximately 15 minutes, the issue won't come back until I turn the car off and then back on.

Has anyone else experienced this? How did you resolve it?

Thanks so much!

Jon

[JD S4]

One possibility is slightly low on brake fluid. This can happen if you have a leak or if your brakes are right at the very end of their life and it's sucking up just a touch extra brake fluid to extend the pads.. Try tossing a tiny bit of brake fluid in the resevoir and then diagnose if you have a leak or need new pads.. A bottle is $5 and it's worth checking. You might be able to "see" your low visually in the resevoid but I've had this happen in the past and it's so miniscule you can't tell. Worth the experiment. Even better if you have some fluid sitting around already

[jonmckeown]

One possibility is slightly low on brake fluid. This can happen if you have a leak or if your brakes are right at the very end of their life and it's sucking up just a touch extra brake fluid to extend the pads.. Try tossing a tiny bit of brake fluid in the resevoir and then diagnose if you have a leak or need new pads.. A bottle is $5 and it's worth checking. You might be able to "see" your low visually in the resevoid but I've had this happen in the past and it's so miniscule you can't tell. Worth the experiment. Even better if you have some fluid sitting around already

Thanks so much for the reply JD. I've checked my reservoir multiple times and it is completely full - almost topped off. Thus the confusion

[A U D I]

Which light is coming on ? The light in the cluster or in the center info screen ? Post a pic if easier.
Depending on the light you might have a brake pad wear sensor going. This can happen even if the pads are good. The wire can get worn from road dirt. Also when checking brake pads, it is sometimes hard to see a problem with a inner pad, however if the fluid level is full this would not be the case.

[jonmckeown]

Which light is coming on ? The light in the cluster or in the center info screen ? Post a pic if easier.
Depending on the light you might have a brake pad wear sensor going. This can happen even if the pads are good. The wire can get worn from road dirt. Also when checking brake pads, it is sometimes hard to see a problem with a inner pad, however if the fluid level is full this would not be the case.

It is the one in the cluster (on the MPH gauge). Fluid level is full - almost at the cap. Last time the brakes were checked, about 3400 miles ago - they had 10MM remaining.

Do you know how would I know which one specifically is going bad since my code reader isn't providing me with any codes?

Thanks for your help! I greatly appreciate it.

[A U D I]

If it was the brake pad sensor it would come on in the center info display screen. Just the brake light coming might be a problem with a rear pad thickness. Was the 10mm also for the rears or just the front ?

[jonmckeown]

If it was the brake pad sensor it would come on in the center info display screen. Just the brake light coming might be a problem with a rear pad thickness. Was the 10mm also for the rears or just the front ?

The Audi Multi-Point Inspection Form says that it is "10mm" for all of the pads.

[A U D I]

I would double check the rears just to be sure. If the brake pump brain was starting to fault it should throw a code in the module for you to read, so it’s hard to think that could be it. If you drive easy does it come on ? Or corner hard would it come on ? Those would go back to low brake fluid, however at 10mm that should not be the case. Are you applying the brakes when the brake light comes on or not touching it at all ?

[jonmckeown]

If I drive easy (low revs) it doesn't come on. Cornering doesn't cause it to come on. I am accelerating when the light comes on. Usually around 2,750 RPMs sustained for a bit. I am not touching the brakes at all when it comes on.

[A U D I]

Maybe a vacuum leak at the booster(?) with the valve not seated 100% or the brake pump brain starting to go.
This is a tough one not to be hands on with.
Keep us posted with any new finds and check out those couple suggestions I gave you.

[jonmckeown]

Maybe a vacuum leak at the booster(?) with the valve not seated 100% or the brake pump brain starting to go.
This is a tough one not to be hands on with.
Keep us posted with any new finds and check out those couple suggestions I gave you.

Thank you very much for your help! I really appreciate it. I'll update the thread as soon as I have it resolved.

[jonmckeown]

Well, it is time for me to eat some humble pie.........

I checked the brake fluid again with my father in law and when you take off the lid it looked absolutely full to me. But, we wiped off the side and held a flashlight to it and the fluid was actually midway between min and max. So, we filled it all the way up and I no longer have the issue. I think this was caused when I accelerated because it moved the fluid back from the center may have been what triggered the warning.

Thank you everyone for your help.

Jon