One for the gurus. 2012 VW Passat Brakes

About a week ago the brake light on my 2012 VW Passat SEL started blinking (which also flashes the daytime running lights). Car has 39,000+ miles. Maybe it’s time for new brake pads?

I’ve also verified that the brake reservoir has fluid AND the level switch has be verified working.


  • The brake disks are all the same temperature after driving (no stuck caliper)
  • No squealing from the pad wear sensors
  • Car DOES NOT pull to one side
  • Light comes on under hot conditions (morning commute is fine)
  • e-brake switch is brand new
  • e-brake signal line DOES NOT short to ground
  • ABS module operates under heavy braking
  • No faults on computer

Any ideas?

Either a bad padwear sensor (located on the driver side front wheel), or pads which are actually low (sometimes squeal tabs don’t squeal like they should) are the most likely candidates on that car.


Since this is a european car . . . doesn’t this car use electronic brake pad wear sensors?

This brake light that is blinking . . .

Do you mean the actual brake lamp(s)?

Do you mean the red brake warning lamp in the instrument cluster?

Or is it some amber colored brake warning lamp in the instrument cluster?

The brake light on the dash cluster & DRL light flash. (see video). I’m not able to see if the brake lamps (on the outside) of the car are flashing. I do know that the DRL lights blink on and off.

So, are the pads worn? What thickness is on each?

Might be a relay failure:

@texases I did a visual inspection of the pads from the top of the caliper. They do not appear to be worn however, this is my first VW so things could be different. I’m used to pads wearing down a lot further but the in pad sensor is a new twist.

I’m going to unplug the wear sensor and see if that makes a difference. If it works then I’ll pull the caliper and check the sensor and measure the thickness from the inside.

@insightful That’s a good idea, too. I’ve tested the 3/85 line at position 1 with the switch disconnected. If there was a shorted diode going to 1/31 the meter should have picked that up. (audible beep).

I think I need page 189. Does anyone know where the 8/86 line terminates?

I did two tests today. Test 1, unplug the brake pad sensor on front left wheel = fail. ABS and anti-lock errors all over the place, even when shunted.

Test 2, shunt the brake fluid level sensor = n/c The dash brake light still flashes over bumps.

Looks like I’m doing pads and rotors tomorrow. fun, fun!


So let me ask a very blunt question . . .

You have not yet removed the brake pads and visually checked if they’re worn down to the level of the electronic pad wear sensor?

For what it’s worth . . . those electronic sensors are usually set up, so that the circuit is complete when the pads are down to 3mm lining thickness, as far as I know

If you’re used to metal pad wear indicators screeching when the pads are down to 1mm, you’ll have to get used to this “new” thing

IF this vehicle thought the E-Brake was actuated (Applied/On) the car would not allow you to drive it. Since this is still a “Fly By Wire” Throttle…the engine computer would not allow the butterfly to operate and thusly…not allow you to accelerate or only putter around but real driving and accelerating would become impossible due to the system thinking that the E-brake is applied.

SO…its not the E-Brake sensor because you would NOT be going anywhere in this car if the system actually thought the e brake was applied. Im not really sure what would cause the situation you are describing here.

I would also look in the owners manual to see exactly what this flashing light is trying to indicate here…Do you have the owners manual? If so…I know what you will be soon reading…either at your computer or while you are on the “Throne” either way…Read that thang. On top of reading the manual… I would prepare to spin some wrenches…just for posterity man.

Im with DB4690 here… I would pull apart the front brakes and have a Looksie…I think one of those sensors on the pads has been triggered somehow. Either by pad wear…or metallic brake dust building up around the pad sensor enough so that it is actually grounding out that sensor. Take the front pads off the car and clean them…wipe off each or THE front pad wear sensor. Those things only cost about 10 bucks so it might not hurt to simply replace it to see whatcha get.


Does that same light come on in normal operation when you set the emergency brake? If so …

Why is the emergency brake switch brand new? Did you recently replace it b/c the original was bad? And did this problem just start happening shortly after? If so, the replacement e-brake switch may be defective.

@db4690 Yes, I visually checked the front pads. Left side was 4cm and the right side was 3.1 cm. There were no sensors on my pads however, the new pads came with a sensor.

@“Honda Blackbird” Is your advice seriously to go RTFM? Electronic e-brakes are so, 2011. (btw- the light in question is for the emergency brake as demonstrated in the video.)