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ABS light and Brake Light flashing - vag-com(diy) or shop?- need insight please?

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  #11  
Old 10-25-2009, 01:59 PM
pengin221's Avatar
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Smile True Anser for VW/AUDI BOSCH ABS trouble, everybody sucking, almost all, may be this

Wrap up: I mean
"Push the sensor all of the way down, and then pull it slowly up about 1.2mm +- 0.6mm. Use a black marker to help with measuring where the top when you have pushed it all of the way down. "

Today I experienced similar thing and I found the true answer!
It seems that so many people change or refurbish ABS system without knowing this!
ABS system and sensor is not gone!
All Bosch car Benz BMW VW AUDI may possibly be the case, if you touched front axle or brake and after that this trouble accurs.
Just think a little, you even do not touch ABS controller,
thereis no reason to break it, especially even integrated circuit
module soldering. There is a big mistake!

The trouble I experienced today is, after working with front gear plug,through front axle, ABS sensor gets on, after running a little bit faster speed. And does not easily go away, and I experienced several time ABS alarm these months...
But today it was so serious, after cleaning front right speed sensor! And sometimes gets off after stopping or running slowly.
I wondered my ABS may be broken!

In my case, simply pushing speed sensor too much too deep, thats it!

Everybody, please note it and keep it in mind!

The answer is "air gap" of the front side BOSCH speed sensor.

My car is AUDI A6 year 2000, but I believe , including all VWs and all BOSCH cars, things are all or much the same.

The trouble is, it seems that rear air gap is prefixed,
but, front air gap is, simply adjustable by putting speed sensor deeper or not!
It's a amazing thing and cannot easily guessed!

People who touch front axle should be careful not to push speed sensor!
But don't worry, if you touched, please do it as follows.

It seems that new speed BOSCH sensor have on top of its head, about 3mm plastic head on top of it. Using that plastic notch, mechanics simply kick in the speed sensor on the hole, installation finishes.

But later on, after extracting that speed sensor, after cleaning, it should not be pushed to the bottom.

In my case, after pushing in to the bottom, I simply dragged about 3mm, both right and left speed sensor. Everything got right! Awesome simple! No ABS alarm!

Today, I experienced just the same trouble during exchanging front gear fluid.
The filler plug was so hard, so, I removed front brake system, and used a breaker bar to open the filler plug, after that I experienced ABS trouble, great shockto me, I wondered, I must refurb my ABS controller reading so may post, but studied so hard, and got the hint, and my Audi went back perfect condition! Simply extracting a little bit, front speed sensor both right and left, It even do not require to remove the tire, simply handling right and left, I could reach the speed sensor, and push in, and a little bit extract, thats it!, No charge! No jack up!

Cleaning speed sensor is also dangerous if you don't now it.
You should unplug the speed sensor just 3mm around from the bottom, after reaching to the bottom, extracting from the bottom. I think you'd better prepare thin head black magic pen, after pushing speed sensor, reaching the bottom, you can mark it, its side, pulling rubber boots of that sensor, so, you can easily adjust about 3mm. I didn't do that because I found it after my car went back,
About 3mm, you don't have to be nervous. In my case, quite vague...

Before knowing that, I did great hustle try to remove my ABS module, and worried about brake oil leak.. when I twisted my ABS 12mm, 13mm pipe, I give away, opening it...
Then I was so lucky to give up to take out ABS module to hustle something!
And I did cleaned my speed sensor and kicked in to the bottom, and I got ABS alarm, but disappeared for a while, after
running 200 km, the next day, I got ABS alarm permanently, and I found the reason, and when I checked the head of speed sensor, its head was shining, touching the magnet rotor, but it was not broken, dragging 3mm apart, both left and right, it worked perfectly, and alarm gone away!

I should add very important information on top,
When I did not pull off my speed sensor, I mean cleaned and plugged deep, both end, once it generate error after running a little bit higher speed, the error alarm occurs, just ignition on, without running the car. It seems that too close to magnet, ABS circuit may know that! And ABS speed sensor have its good gap range 2-3mm around, I don't know precise value, its self, by its some scientific reason.



http://www.sjmautotechnik.com/troubl...ing/brake.html

As this url says, new front speed sensor comes with a PVC tip on top, that is the key.
This picture one may be some older version, but as for the situation, there is no difference.



This picture one is the same as my Audi A6 one, it seems to have no PVC tip on top. Speed sensor itself just looks like a metal rod. You can fix it by finding, 1mm thick, some appropriate small plastic tip around you, using instantaneous bond to attach on top of it.

In my case, metal head of my speed sensor is shining, worn a bit central portion, because I plugged too deep, just to the bottom, never imagine and, not knowing that the sensor head is direct hitting the magnetic rotor!, to my mistake.
But it was not broken when I noticed, and fixed it, and my alarm gone away.....

Another possibility to worry before worrying about ABS control center trouble is, cable trouble, in such case, you can not easily recover from ABS error, after re-ignission, and you may not experience alarm light on on some high speed. I highly recommend to check air gap, before you suspect control module, in case you can recover from alarm after a while, parking.

Every body touching front axle, having VW Audi, BenZ BMW or BOSCH ABS, should know that! If it does not work, then after worry about other serious trouble about ABS its self.
 

Last edited by pengin221; 10-29-2009 at 01:46 PM.
  #12  
Old 10-25-2009, 09:47 PM
milo55041's Avatar
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Thread Starter
Join Date: Apr 2007
Location: Rochester, Minnesota
Posts: 91
Default Your kidding?

Originally Posted by pengin221
Sorry for multipost, you are also the same case!

Today I experienced similar thing and I found the true answer!
It seems that so many people change or refurbish ABS system without knowing this!
ABS system and sensor is not gone!
All Bosch car Benz BMW VW AUDI may possibly be the case, if you touched front axle or brake and after that this toruble accur.

The trouble I experienced today is, after working with front gear plug,through front axle,
ABS sensor gets on, after running a little bit faster speed. And does not easily go away,
And I experience several time ABS alarm these months... But today was so serious!
I wondered My ABS gone!
And sometimes gets off after stopping or running slowly.

In my case, simply pushing speed sensor too much too deep, thats it!

Everybody, please note it and keep it in mind!

The answer is "air gap" of the front side BOSCH speed sensor.

My car is AUDI A6 year 2000, but I believe , including all VWs and all BOSCH cars, things are all or much the same.

The trouble is, it seems that rear air gap is prefixed,
but, front air gap is, simply adjustable by putting speed sensor deeper or not!
It's a amazing thing and cannot easily guessed!

People who touch front axle should be careful not to push speed sensor!
But don't worry, if you touched, please do it as follows.

It seems that new speed BOSCH sensor have on top of its head, about 3mm plastic head on top of it. Using that plastic notch, mechanics simply kick in the speed sensor on the hole, installation finises.

But later on, after extracting that speed sensor, after cleaning, it should not be pushed to the bottom.

In my case, after pushing in to the bottom, I simply dragged about 3mm, both right and left speed sensor. Everything got right! Awesome simple! No ABS alarm!

Today, I experienced just the same trouble during exchanging front gear fluid.
The filler plug is so hard, so I removed front brake system, and used a breaker bar to open the filler plug, after that I experienced ABS trouble, great shock, but studied so hard, and got the hint, and my Audi went back perfect condition! Simply extracting a little both right and left, It even do not require to remove the tire, simply handling right and left, I could reach the speed sensor, and push in, and a little bit extract, thats it!, No charge! No jack up!

Cleaning speed sensor is also dangerous if you don't now it.
You should unplug the speed sensor just 3mm around from the bottom, after reaching to the bottom, extracting from the bottom. I think you'd better prepare thin head black magic pen, after pushing speed sensor, reaching the bottom, you can mark it, its side, pulling rubber boots of that sensor, so, you can easily adjust about 3mm. I didn't do that because I found it after my car went back,
About 3mm, you don't have to be nervous. In my case, quite vague...

Before knowing that, I did great hustle try to remove my ABS module, and worried about brake oil leak.. when I twisted my ABS 12mm, 13mm pipe, I give away, opening it...
Then I was so lucky to give up to take out ABS module to hustle something!
And I did cleaned my speed sensor and kicked in to the bottom, and I got ABS alarm, but disappeared for a while, after
running 200 km, the next day, I got ABS alarm permanently, and I found the reason, and when I checked the head of speed sensor, its head was shining, touching the magnet rotor, but it was not broken, dragging 3mm apart, both left and right, it worked perfectly, and alarm gone away!

Every body touching front axle, having VW audi, or BOSCH ABS, should know that! If it does not work, then after worry about other serious trouble about ABS its self.

Your kidding? Wow...amazing find. How did you figure this out again?

So what you are saying is: Push the sensor all of the way down, and then pull it slowly up about 3mm. Use a black marker to help with measuring where the top when you have pushed it all of the way down.

I had to take out my wheel sensors to work on my axle, and then I got the ABS service light on and the red flashing BRAKE light. So you're saying that doing this may fix my issue?

Thanks.

SM
 
  #13  
Old 10-26-2009, 04:17 AM
pengin221's Avatar
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Join Date: Aug 2009
Posts: 7
Default Yeeeeeeeeeeeeeeees!!!

Sure, you are right!!!!!!!!!!!!
No hustle!!!!!!!!!!!!
Thats it!!!!!!!!!!!!!!
I will find some stock new speed sensor photo later, so you'll get it more seriously!!!
 
  #14  
Old 10-26-2009, 04:43 AM
pengin221's Avatar
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Join Date: Aug 2009
Posts: 7
Default



http://www.sjmautotechnik.com/troubl...ing/brake.html

As this url says, new front speed sensor comes with a PVC tip on top, that is the key.

I could not find any good new front speed sensor picture.
In my case, my head of speed sensor is worn a bit, because I plugged deep, to my mistake. But it was not gone wrong when I found it, and everything go back.....
I'm fine now!
 

Last edited by pengin221; 10-26-2009 at 05:50 AM.
  #15  
Old 10-27-2009, 06:45 PM
milo55041's Avatar
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Thread Starter
Join Date: Apr 2007
Location: Rochester, Minnesota
Posts: 91
Default

Originally Posted by pengin221


http://www.sjmautotechnik.com/troubl...ing/brake.html

As this url says, new front speed sensor comes with a PVC tip on top, that is the key.

I could not find any good new front speed sensor picture.
In my case, my head of speed sensor is worn a bit, because I plugged deep, to my mistake. But it was not gone wrong when I found it, and everything go back.....
I'm fine now!

So this is the picture of a ABS speed sensor for my car. As you can see, it is only made out of a metal piece, at least what it portrays here. So, I wonder how the 3mm rule applies to this??

[IMG]file:///D:/DOCUME%7E1/SMILOS%7E1/LOCALS%7E1/Temp/moz-screenshot.png[/IMG][IMG]file:///D:/DOCUME%7E1/SMILOS%7E1/LOCALS%7E1/Temp/moz-screenshot-1.png[/IMG][IMG]file:///D:/DOCUME%7E1/SMILOS%7E1/LOCALS%7E1/Temp/moz-screenshot-2.png[/IMG]
 
Attached Thumbnails ABS light and Brake Light flashing - vag-com(diy) or shop?- need insight please?-oem-front-abs-speed-sensor.jpg  
  #16  
Old 10-27-2009, 09:23 PM
pengin221's Avatar
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Join Date: Aug 2009
Posts: 7
Smile air gap is the key!

http://www.bosch-motorsport.de/pdf/s...speed/IA-C.pdf
As this document says air gap play a important role to generate output pulse voltage. If the gap is too short sensor may generate too big pulse,
and left and right voltage balance may also have some problem, for ABS module computation.

bosch original site recommends 0.5 to 1.8mm for some sensor.
0mm is no good. 0.5 to 1.8mm may be the best suit value, for some bosch sensor.

http://rb-k.bosch.de/en/powerconsump...eedsensor.html


In my case I adjusted 3mm around reading some other document, and I think I must correct to the value above!

As I said new stock one have pvc tip on top to adjust, after installation it goes away worn by, rubbed by magnetics heads. In my case mine was shining and a littlebit worn its flat head, by pushing hard too deep in the hole.

So, please search google with air gap, speed sensor and Bosch, you can find details what I mean.
 

Last edited by pengin221; 11-01-2009 at 07:49 AM.
  #17  
Old 10-27-2009, 09:39 PM
carbonOX's Avatar
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Join Date: Oct 2009
Location: Idaho
Posts: 258
Default

I will have to try all this out. My abs light has been on sice I got my car with the flashing brake light. I havent bothered with it since it hasnt effected the braking. Now I know the fix to this little annoyance
 
  #18  
Old 01-30-2011, 08:26 PM
erasmmuss's Avatar
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Join Date: Jan 2011
Location: Phoenix AZ
Posts: 213
Default

ok after reading this post 3 times i did not understand nothing u suppose to pull push the dam thing or buy a new speed sensor ?
BTW i have the same issue after a brake pad and rotor change
 
  #19  
Old 03-24-2011, 09:33 AM
gapon's Avatar
1st Gear
Join Date: Nov 2006
Posts: 5
Default funny this happend to my s4

funny this happened to my 2000 s4 right after changing my rotors and brake pads i start noticing some problems. i really hope this is my case. ill work on it on my day off... anybody knows if its safe to drive if the ABS and Brake light flashes?
 
  #20  
Old 11-03-2012, 12:56 AM
Bae Min Chul's Avatar
1st Gear
Join Date: Oct 2012
Posts: 1
Default

Is anybody can tell me where the speed sensor is?
Mine is audi 2005 a6 and i have exact same problem.
I already changes brake light switch but it still annoy me.
I really want to repair it.
Can any body help me?
 


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