Hey guys, I also got the brake pressure sensor warning and advised to stop driving. Unfortunately, I did a few small trips and then eventually had to park the car up due to personal reasons. I attempted to replace the sensor with a cheap one off eBay and did that a couple of times, I think the seller kept saying they’re defective and kept sending me replacements. 
 

After two attempts, I had enough and decided to go to a garage. The garage charged me £300 for OEM. However, the brake light is still on, the garage told me to drive it for 200 miles and this should reset the warning lights. If it doesn’t it could cost me dear… I was wondering if this happened to anyone else?

£300!!!!!

That is an absolute rip-off!!!! 

I paid approximately £90 for the OEM part from Audi and swapped it myself in 2 minutes!

From my memory, I can remember if the warning message on the dash cleared straightaway without clearing the code with my scanner.

Is there still a warning message on the dash?

I don't recall the brake light staying on as being a symptom

£300 is a rip off. I also paid £90 for a sensor from an Audi main dealer and replaced it myself in minutes.

Once swapped all warnings ceased for me.

Yeah I’m still getting the warning of brake pads wearing thin and brake fault, etc. 

I wish I just grabbed the part from

the main dealer and fitted it myself. It is literally straight forward. I’m worried now, I’m not sure if driving cycles will help, I’ll give it a go…

It sounds like the warning that the 'brake pads' are wearing thin is a separate issue.

If you at least get the pads checked and replaced if necessary first, then see if that light goes out and go from there

Have the brake pads been checked to see if the wear symbol is correct?

Regards,

Gareth. 

I’d hope so, I’ve literally just took it in had the service, MOT and pressure sensor passed. The garage literally told me to see if the warning will reset itself with 200 miles driven. 
 

I think in hindsight as soon as the brake sensor pressure warning came on I wish I just got the sensor replaced. I’m not too sure what is going on. Although it is driving perfectly well…

28 minutes ago, ShyMan456 said:

I’d hope so, I’ve literally just took it in had the service, MOT and pressure sensor passed. The garage literally told me to see if the warning will reset itself with 200 miles driven. 
 

I think in hindsight as soon as the brake sensor pressure warning came on I wish I just got the sensor replaced. I’m not too sure what is going on. Although it is driving perfectly well…

this warning came on my screen and went away but eventually there was too much play bad feeling when braking after looking the forum it was the brake pressure sensor I bought one from amazon and changed it myself using YouTube and it fixed but it only applies to the brake pressure sensor not any other braking issue!!!

Fair man, I’ve replaced the sensor. It just hasn’t cause the warnings to go away. I’ll drive it some more and see if it resets with drive cycles like the mechanic says. If it doesn’t I’ll have to go back in, it might be the ABS is knackered and causing the brake lights to flash…

Does the brakes feel any different?

Nope. Literally still smooth. Rides the same as well, smooth as I’ve ever known it

Cool. Maybe the warning will clear after enough cycles.

If the ABS system is bricked, don't be too alarmed.

Although it's not ideal, you can send off the ABS unit to a company that resets it for a fraction of the cost of a new unit (around £3-400). I posted the link to the company in an earlier post in this thread (go back a few pages).

You'll need a mechanic to remove the part though, so you'll be without use of the car until it's put back on....

Cheers pal, I really appreciate your time and support. Thanks a lot

Just to add my two cents, 2016 A4 Avant b9 190 quattro 100k miles

C11EC04 with the dash bit saying brakes restricted / start stop gone etc etc. It popped up as soon as I started the car and was after the car hasn't been used much in the last two weeks and perhaps nor for 3 days before that (seems common that if they sit the sensor dies). I drove it 10 mins and then came home as I knew it could brick the ABS eventually.

I work on cars alot and even this got past me..

I changed the sensor to a new one from amazon £15, upon plugging it in I had the exact same code. I fiddled with it on and off the car, I then started getting codes for brake boost pressure sensor short to GND and short to POS, sometimes one, sometimes the other, sometimes combined with C11EC04 sometimes not. For reference C054B00 is the code for GND or POS I forget which. So sometimes that code by itself and sometimes that combined with C11EC04.

I thought perhaps it was my ABS unit dying as I knew the sensor was good and I also tried an exact same oem audi sensor from my A6 C7 for good measure, same code games. And my amazon sensor worked fine on the a6 c7.

Long story short (haha) the sensor was not plugged in correctly. It was not quite seated enough. I removed the rubber seal (car side plug) and seated the sensor properly, this time making sure it latched fully. All cured.

To add, it was actually semi latching the first time and visually it looked normal, it pushed most of the way in and it wouldn't pull off from a small tug, making me believe it was properly on.

Before you mess around try using a needle and working the small white rubber water seal out, and making sure the car side clip is fully backed off then push the sensor on all the way, latch it properly (it shouldn't be able to be pulled out at all by any tugs) and then plug the sensor back into the car brake booster reservoir.

I knew before I started it again that the problem was solved. It just wouldn't yank off this time like I could before, and the short to gnd and pos suddenly all made sense.

Goodluck !