New brake switch no good or bad install

Iowa TDI

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Dec 5, 2017
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2014 TDI Vert Beetle
So I installed a new brake switch, no I didnt read and get a VW one before I ordered it. Anyway, its installed, taillights still on all the time. Is the switch I just put in bad? The white part that sits close to the master cylinder does that have some sort of sensor in it? It fit pretty snug and kind of snapped into place. If i have to buy a genuine VW one that fine. Just trying to figure out why this new one isnt working. Im heating up the trans fluid now and will pull relevant codes again. Just frustrating but may be totally my fault for buying a rockauto part. Live and learn.
 

Iowa TDI

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Dec 5, 2017
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IOWA
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2014 TDI Vert Beetle
Looking for a little guidance now. Replaced 1 rear brake bulb with the proper wattage one, checked the rest of the bulbs, all looked good and had unbroken filaments. Rear brake lights still on all the time. New brake switch installed. I jiggled the brake pedal and kind of pulled it out pretty hard...the brake lights shut off and blinking glow plug shuts off instantly! Is there some adjustment that I can do to that pedal? All this scanning and headaches and it would seem the brake pedal isnt releasing all the way from whatever switch is activates. Thanks in advance.
 

Iowa TDI

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2014 TDI Vert Beetle
Tried adjust the brake pressure switch with VCDS, it said i could not. Brake pressure when switch is supposed to be off (like a normal removal of your foot from the pedal) is .64 bar, but the switch is still activated. When I yank it forward hard and it deactivates, it briefly goes to .40 bar, but then returns to .64 but is still deactivated according to the vcds. Funny thing, I was easily able to get it to deactivate when i yanked it back with my hand on flat ground, but on a slight incline no matter how hard I yanked out on the pedal, it would not deactivate the switch. Back on flat ground, no problems. This car is possessed. Anyone have any ideas? Oh yes, Happy Easter.
 

Seatman

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2014 Skoda rapid elegance 1.6 cr tdi
Take the switch out, of the bracket and plug it in, then check and see if the switch works by hand, if so then it's an install issue.
 

Iowa TDI

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2014 TDI Vert Beetle
Take the switch out, of the bracket and plug it in, then check and see if the switch works by hand, if so then it's an install issue.
If the brake switch is installed incorrectly then I would think it would never work. Why does pulling the brake pedal up hard, cause it to work? I have been looking online for any sort of an adjustment on the brake pedal to let the plunger come out of the brake booster further. I will pull the switch and try it not mounted. I have my doubts as the VCDS was seeing what it needed to be activated or not depending on the brake pedal. Id really like to find some info on how the mounting position of the switch affects its use. There is really no bracket that I can see. Just the way the master cylinder is molded, it kind of is wedged in there. There isnt anything that I can find on any forums about this. Nothing on brake pedal, nothing on brake booster adjustment and it doesnt appear to be a booster failure of any sort. I would love to find some reading on how the system works, like brake is pressed, plunger goes in, this sends fluid to activate the brake switch or? Like I said, it crickets on the ole web on this topic. Not sure if the info I seek is on the erWin vw stuff that you can buy.
 

Seatman

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2014 Skoda rapid elegance 1.6 cr tdi
There should be a bracket with a round hole and a couple of cutouts for locating the tabs, you push it in then twist and it clicks into place.

Mk4 golf


New beetle, both the same

 

Iowa TDI

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2014 TDI Vert Beetle
Thanks but that is not the brake switch on a 2014 Beetle. It mounts on the master cylinder.
 

sdaly426

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Feb 6, 2024
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Eastern Ohio
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Jetta
I’m battling the same thing. Mine is on the master though. I just posted a thread regarding my issues.
please read it and give me some advise before i set this car on fire! Lol
 

Iowa TDI

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2014 TDI Vert Beetle
This IS the 2012 new beetle forum. I dont know how to change that in my profile. In the 1st post and 5th post I clearly talk about how the switch mounts to the master cylinder. Im not sure how that constitutes failure on my part, but ok.
 

Iowa TDI

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IOWA
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2014 TDI Vert Beetle
I’m battling the same thing. Mine is on the master though. I just posted a thread regarding my issues.
please read it and give me some advise before i set this car on fire! Lol
Ive been advised that this could be more of a mechanical issue than a brake switch issue. Mine is also on the master cylinder. The switch is good and doing its job. I will take apart the brake pedal assembly and see if it just needs cleaned up to allow it to retract fully under brake booster pressure.
 

Seatman

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Apr 23, 2010
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2014 Skoda rapid elegance 1.6 cr tdi
This IS the 2012 new beetle forum. I dont know how to change that in my profile. In the 1st post and 5th post I clearly talk about how the switch mounts to the master cylinder. Im not sure how that constitutes failure on my part, but ok.

People like myself just hit the new posts tab, the particaular section isn't clear so I just go off info in the first post or the info up the left side.


To change your info on pc at least, just click your profile pic up top right side area and it should take you right you account info.
 

Lightflyer1

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Round Rock, Texas
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2015 Beetle tdi dsg
This IS the 2012 new beetle forum. I dont know how to change that in my profile. In the 1st post and 5th post I clearly talk about how the switch mounts to the master cylinder. Im not sure how that constitutes failure on my part, but ok.
Usually considered good etiquette to post the year and model you have in your post, just so everyone is sure what you are talking about. One year may not be the same exactly as another. As you see you confused more than myself. People post in the wrong forum all the time as well. No problem as now everyone knows.
 

Iowa TDI

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2014 TDI Vert Beetle
Well Im pc illiterate and apparently also VW illiterate. Went to take the drivers seat out so I can have some room to get under the dash to try to see how the brake pedal pivots and decided against it because my luck, the airbag would blow apart. I dont see anything that would be a restriction on the brake pedals ability to go back in the " home " position. I dont know if the rod that comes out of the brake booster is wedged in the back or what. I was going to take the bolt that goes thru the brake pedal out but im a bit leary taking things apart that I cant get eyes on. All I know is this is a stupid problem to have. If it would just come out like another mm it woukd be fine. I squirted some penetrating oil on the bolt but not sure it did anything.
 

Iowa TDI

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2014 TDI Vert Beetle
Is the brake booster responsible for creeating the pressure to push the brake pedal back? I got under there and used compressed air to try to blow any debris out and sprayed it with penetrating oil. I see nothing wrong. I cant even find an exploded diagram of the brake pedal assembly online. Everything online is old beetle stuff. Im trying to figure out what the " stop" is that keeps the pedal from coming back up too far. There is a bar under there but its not even close to hitting that. Is it supposed to be close the the bar? Im about 1/2" from it.
 

Iowa TDI

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2014 TDI Vert Beetle
Well now Im dead in the water...there is a mount and a bearing shell that the brake booster rod ball head attaches to. Cant get that apart without a special vw tool T10159. Looks like the booster rod ball head snaps into place just by pushing the brake pedal into it upon reassembly. That tells me that there is no real adjustment or anything that can inhibit the brake pedal from coming forward, and its travel back to the "home" position is decided by the amount of travel the brake booster rod gives it. If anything were worn out then the rod would actually extend deeper into the bearing shell and definitely shut off the brake switch, not the opposite. I have been turning wrenches on domestic cars for 35 years but this is just goofy. I'm not sure if I need at look at the brake booster at this point or not. I don't get any codes or any hissing or indication on the VCDS that there is a brake booster issue. I dont want to take it to VW because they will just charge me $169hr to get to the point I am already at. Am I wrong on the brake booster idea? It seems to be the item that controls the travel of the booster rod, nothing else. I assume the bar that I said I was 1/2" from, its there to keep the rod from getting overextended out of the brake booster if the pedal would somehow get pulled out. Anyway, thanks for any replies, this car is down to this one last thing and its kicking my arse. Also I figured out how to change my profile thing.
 

Seatman

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2014 Skoda rapid elegance 1.6 cr tdi
I read that the new beetle set up is similar to the mk7 golf? Apparently it has a fail safe so if some part of the circuit isn't right the brake lights will stay on. Can be a bad wire or a bad fuse.

Post no 6 in this thread

 

Iowa TDI

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2014 TDI Vert Beetle
I read that the new beetle set up is similar to the mk7 golf? Apparently it has a fail safe so if some part of the circuit isn't right the brake lights will stay on. Can be a bad wire or a bad fuse.

Post no 6 in this thread

Thank you! That will give me another avenue to pursue. I checked what I thought were pertinent fuses but now that I have all the erWin stuff I can see which fuse is for what. A fuse would be an always on or off situation I think though. Heck i dont know at this point. As an update, I have a little Milwaukee camera and I stuck it back up behind the brake pedal. Nothing looked odd or worn. I downloaded all the stuff I could from erWin on this 2014 beetle and looked thru the brake stuff, nothing jumped out at me. As a last resort I pulled out the brand new brake switch I just installed a week ago, and yes the brake lights default to "on" like the post about the Golf 7 above. No brake switch installed equals brake lights on. That tells me that the car isnt always recognizing that the brake switch is present. I looked at where the brake switch mounts on the master cylinder with the camera and followed the wire into the bigger wire loom. I saw nothing to indicate broken or even frayed wire. I then installed a brand new VW OEM switch. And yep brake lights still on! It can be turned off if you push down the brake pedal by hand and then yank up on it. it wont work if you just try to yank up on it. I think you need the momentum of pushing it down first. The way the brake switch mounts seems pointless. I see no reason for it to be mounted under the master cylinder. I don't see where it is getting any "info" from the master cylinder. It could easily be mounted on the firewall directly under the wire loom it feeds in to. I tested both switches with a Fluke multi meter, they are not bad and the one I took out and threw away most likely wasn't either! The only thing I can fathom is there is a nick in a wire somewhere that is not allowing the circuit to close. There is an plastic box of some sort right on top of the brake pedal. Maybe I need to be looking at that since the yanking of the brake pedal seems to help the situation, but not 100% of the time.
 

Iowa TDI

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2014 TDI Vert Beetle
Here is my brake fault code from VCDS:

001393 - Brake Switch (F)
P0571 - 000 - Implausible Signal - MIL ON
Freeze Frame:
Fault Status: 11100000
Fault Priority: 2
Fault Frequency: 1
Reset counter: 255
Mileage: 197758 km
Time Indication: 0
Date: 2017.12.30
Time: 13:45:02

Freeze Frame:
RPM: 1771 /min
Speed: 17.0 km/h
Load: 42.0 %
Voltage: 13.60 V
Torque: 207.0 Nm
Hex Value: 0xFF02
Bin. Bits: 00001001

And 1 other that may or may not be part of the issue:

001674 - ECM Power Relay Load Circuit
P068A - 000 - Opens Too Early - Intermittent
Freeze Frame:
Fault Status: 00100000
Fault Priority: 2
Fault Frequency: 5
Reset counter: 255
Mileage: 0 km
Time Indication: 0

Freeze Frame:
RPM: 0 /min
Speed: 0.0 km/h
Load: 0.0 %
Voltage: 0.00 V
Hex Value: 0xFF00
Bin. Bits: 00000000
Temperature: -90.0°C

I also have an engine immobilizer one but I believe thats from taking the battery in and out 50 times lately.
 

Iowa TDI

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Dec 5, 2017
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IOWA
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2014 TDI Vert Beetle
Drove the car about 80 miles today, brake lights on the whole time:). I noticed when I went to stop after 30 miles of highway the brake pedal seemed to go pretty far down before grabbing. I quick let up and stabbed it again and it had a lot more pressure. Is this a bad brake booster possibly and the source of all my woes? I did notice that when I was under the dash that there was a definite space between where the edge of the booster is and the puck Ill call it that slides in and out with the pedal. On pics I have seen of new ones, there is no gap. Booster is $300, I hate to change it and have it not fix the problem. Other than that car drive hreat and have put over 100 miles on it. Not sure on the mpg thing, is comes back average of 40 after the 80 miles of highway,but who knows.
 

Iowa TDI

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Dec 5, 2017
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2014 TDI Vert Beetle
So sitting in the car, car off and I pump up the brakes...pedal slowly goes down. Pump them back up, start the car and the pedal goes down slowly. Leave the car running and pump the brakes up again, pedal slowly goes to the floor and literally bottoms out. Not sure if this is the vacuum pump or brake booster. One of them being bad might be the reason for the booster to not be pushing the brake pedal back to home position and shutting of the brake lights. Have a vacuum gauge but its old. Hopefully i can jerry something together to get a vacuum reading.
 

Iowa TDI

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Dec 5, 2017
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IOWA
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2014 TDI Vert Beetle
22" of vacuum at vacuum pump. So at least the pump is eliminated. Now to test the hose that goes to the brake booster. I guess if it tests the same then its the brake booster. Unless I am overlooking something.
 
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