# Traction control, ABS, and e-brake light come on when I hit bumps



## Checkers10160 (Jun 4, 2013)

So lately whenever I hit bumps (I live in the Northeast, where our roads are ****) my Traction control, ABS, and e-brake lights come on for a few seconds, and the car beeps at me. It started with only hard bumps, but it's been taking less and less to trigger it. This tells me that something is loose, and getting looser, but I have no idea where to look. Is there even anything that would control all three of these things? The traction control and ABS I get, but having the e-brake light go on too seems weird, and Google doesn't show anyone else with all 3 problems, just the first two. My only thought on that is my car needs rear brakes. I was changing all of them, but the fronts took longer than expected so the rears are still worn down. Could that affect any of this? And if it is some sort of brake sensor, where would it be? Thanks everyone


----------



## Boulderhead (Oct 21, 2012)

Checkers10160 said:


> So lately whenever I hit bumps (I live in the Northeast, where our roads are ****) my Traction control, ABS, and e-brake lights come on for a few seconds, and the car beeps at me. It started with only hard bumps, but it's been taking less and less to trigger it. This tells me that something is loose, and getting looser, but I have no idea where to look. Is there even anything that would control all three of these things? The traction control and ABS I get, but having the e-brake light go on too seems weird, and Google doesn't show anyone else with all 3 problems, just the first two. My only thought on that is my car needs rear brakes. I was changing all of them, but the fronts took longer than expected so the rears are still worn down. Could that affect any of this? And if it is some sort of brake sensor, where would it be? Thanks everyone


I would do the following if you can. There are no wear sensors on the rear that would cause the lights to come on.

1. Scan for any codes using VCDS
2. Check wheel speed sensor wiring for cuts / breaks
3. Check output from your alternator using a multimeter and verify all your grounds are solid.

These symptoms would concern me as you aren't going to have use of ABS or traction control with the lights on...


----------



## Checkers10160 (Jun 4, 2013)

Boulderhead said:


> I would do the following if you can. There are no wear sensors on the rear that would cause the lights to come on.
> 
> 1. Scan for any codes using VCDS
> 2. Check wheel speed sensor wiring for cuts / breaks
> ...


Thanks for the reply! I'm not sure what VCDS is though. Vag Com Diagnostics Scan, maybe? I don't have access to one :-\ The lights only stay on for a second or two, so I'm not sure if they would be retained. I've scanned it with Torque and it's not throwing any codes. If I remove the wheels, will the speed sensors be fairly obvious?


----------



## lite1979 (Sep 9, 2005)

VAG-COM, yes. Generic OBDII scanners only report emissions related fault codes. VCDS, aka VAG-COM, can access other systems, including braking and all-wheel-drive. If you have a wheel speed sensor that cuts out intermittently, it should show up in VAG-COM and give you an idea of where to look.


----------



## Boulderhead (Oct 21, 2012)

Checkers10160 said:


> Thanks for the reply! I'm not sure what VCDS is though. Vag Com Diagnostics Scan, maybe? I don't have access to one :-\ The lights only stay on for a second or two, so I'm not sure if they would be retained. I've scanned it with Torque and it's not throwing any codes. If I remove the wheels, will the speed sensors be fairly obvious?


If u will be working on this car yourself then I would suggest adding that to a list of items to pick up as it can save hours upon hours trying to debug a problem. The speed sensors are obvious as they are a sensor embedded in the hub. Do a google image search for Audi TT wheel speed sensor and u can get a better idea of what ur looking for.


----------



## TommyTT (Jul 10, 2012)

Ive got the exact same problem, pinch/tear in a ABS/Wheel Speed Sensor wire.
Left front for me, but you'll need to vag-com it to be sure.
new harness was $120 Canadian from the dealer


----------



## Boulderhead (Oct 21, 2012)

You can repair the harness instead or replacing and another thing to check is for any debris that might be attached to the magnetized sensor and clean up the ends with an abrasive pad.. Just be gentle and be careful removing the sensors from the hub.


----------



## eskimo87 (Sep 11, 2013)

ive had exact same issue, it was due to loose ECU harness. Once properly reinstalled it was fine


----------



## Checkers10160 (Jun 4, 2013)

Thanks for all the replies everyone. SO I'm fairly certain it's the front left wheel that's causing it, and I just found out I have a bad wheel bearing on that same whee. Could that be the cause?


----------



## lite1979 (Sep 9, 2005)

A bad wheel bearing will definitely allow some play between the wheel speed sensor and the ABS ring on your hub. I had one go last summer, and before I replaced it, abs would engage almost 100% of the time in the last few feet before a complete stop.

Sent from my XT907 using Tapatalk


----------

