Can I catch a break!
Well, everything was going great until around the time that I reached the 500-mile mark of road time. All of a sudden my instrument cluster lights up like a Christmas tree. Not one but three warning lights all associated with the brake system illuminate out of nowhere.
I am all about quick and easy fixes because the less time I spend fixing is more time I have driving. Also the easier the fix usually equates to less money spent, but that goes back to troubleshooting 101. Start with the most basic components and the ones most likely to fail – fuses and sensors.
My OBDeleven is pointless to me at this point because it is not showing any faults with the ABS system. Not sure what’s going on there, so my next go-to resource is Google. I do a quick internet search for ABS, Traction Control Light on, and of course, thousands of results returned.
I am looking at URLs from the most relevant forums – passatworld.com or Audi forums. I find a thread on passatworld that talks about the ABS module being at fault. The fault is associated with a flashing brake warning light. Also in the post, the wheel speed sensor is mentioned along with the same warning lights that I have.
As I mentioned earlier all the lights lighting up at the same time usually point to one component. In the case of the brake and ABS system, the main component responsible for the system is the ABS Control Module. But this is not a part that is easily replaced. Since I have steady warning lights and not a flashing brake light I can check that part off as not being the fault – for now.
First off I need to work my way backward and ask myself the question has anything been done to the brakes? In fact, I replaced both front and rear brake calipers. Installed new pads and had the rotors turned. That might explain the brake pad warning light but not the ABS or Traction Control light. The only other component in the area where I had recently done any work is the ABS wheel speed sensor.
So from the research that I have done and the previous work accomplished this is the first thing that I am going to check.
ABS Wheel Speed Sensor
The front wheel speed sensor sits behind the rotor and dust shield on the forward end of the steering knuckle. The sensor has a magnetic pickup just like the RPM sensor that senses the rotation of the outer CV joint spindle as pictured.
So, perhaps working around in that area caused some debris to interfere with the magnet on the sensor. So the simplest and easiest way to check the sensor is to pull it and clean it. The sensor is not held in with any bolts and can simply be removed by hand. Or so I thought!