# Beeping sound/bliking light when braking/accelerating



## silver_arrow_jetta (Jul 30, 2004)

Everytime i brake hard or accelerate quick my brake light flashes followed by a beeping sound







. Wondering if anyone ever experienced this symptom before. Is my masrter cycilinder going? car in question is a Mk4 with mk20 ABS system. thanks http://****************.com/smile/emthup.gif


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## larrylarr80 (Mar 4, 2005)

*Re: Beeping sound/bliking light when braking/accelerating (uniblk)*

I HAVE EXPERIENCE WITH THIS ARE THERE ANY FAULTS BUT FIRST CHECK YOUR BRAKE FLUID LEVEL MAKE SURE THERE IS MEAT ON THE PADS IF MECHANICALY ALL IS WELL IT MAY BE ELECTRICAL IM ME LET ME KNOW THE RESULTS.


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## silver_arrow_jetta (Jul 30, 2004)

brake pads are fine, fluid is at level. Thinking either ABS pump or master cilynder


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## phatvw (Aug 29, 2001)

*Re: (uniblk)*

Which brake light? Which beep?
Is it the same light/beep that happens when your handbrake lever is UP? If so, you need to replace the handbrake switch which is mounted under the handbrake lever. See interior FAQ in the MkIV forum for instructions on disassembling the appropriate plastic panels. Swapping the switch is plug and play once you have the plastic panels off.


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## DIAF (Sep 17, 2005)

I've recently gotten the same beep. It is the same dash light that goes on with the hand brake, but that also means it's the same light that comes on for any brake malfunction (low fluid, burned out tail-light, setting off the wear indicator on the pads).
I scanned mine with an OBD-II tool, and it came up with nothing. I did a vag-com scan (I only have the freeware), and it said something about an abs sensor failure. 
Mine is sporadic, and only seems to happen during hard acceleration or cornering. My issue is not consistently repeatable...otherwise I would have figured it out by now.


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## phatvw (Aug 29, 2001)

*Re: (DIAF)*

The handbrake light is DIFFERENT than the one that comes up for low fluid/low brake pad/ABS malfunction.
Your problem is the handbrake switch. Its a ~$3 part at the VW dealer. Easy to fix.


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## DIAF (Sep 17, 2005)

If I remove the top of the brake fluid reservoir, it's the same light on the dash that shows low fluid....perhaps they're different from the 2001.5's to the 05's?


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## phatvw (Aug 29, 2001)

*Re: (DIAF)*


_Quote, originally posted by *DIAF* »_If I remove the top of the brake fluid reservoir, it's the same light on the dash that shows low fluid....perhaps they're different from the 2001.5's to the 05's?

Oh I wonder if it depends on what gauge cluster you have. I believe mine flashes STOP LOW BRAKE FLUID when there is low fluid and there is a separate light for the low brake pad. For the handbrake there is just BRAKE in tiny red letters and an accompanying beep beep beep if the car is traveling faster than ~6MPH.
But mine is GLX trim with fancy heads-up display cluster and MPG ratings etc.
I bet for GL/GLS trim where you don't get the nice heads-up display, it does something different.


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## DIAF (Sep 17, 2005)

I don't have the MFA on my 1.8t (GLS), and all I get is the small red text that says "BRAKE".
So back to the drawing board


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## silver_arrow_jetta (Jul 30, 2004)

does anyone happen to have the part number for that e brake switch?


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## phatvw (Aug 29, 2001)

*Re: (uniblk)*


_Quote, originally posted by *uniblk* »_does anyone happen to have the part number for that e brake switch?

Not sure. But here are the directions to extract the part and check for yourself:
http://forums.vwvortex.com/zerothread?id=958556
Step #17 shows the switch.
When you check, post the part number here http://****************.com/smile/emthup.gif


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## silver_arrow_jetta (Jul 30, 2004)

will take it apart and check the part number


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## silver_arrow_jetta (Jul 30, 2004)

i have the e brake swithc replaced and i still get the ****ing beep!


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## silver_arrow_jetta (Jul 30, 2004)

anyone else?


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## DIAF (Sep 17, 2005)

*Re: (uniblk)*

Oddly, this morning it happened to me again...twice.....two hard braking incidents (NJ drivers







)...beep followed by the light blinking.
Fluid is fine, pads are 90%, lines are solid....pedal went to floor, but the car stopped like I had a tailhook on an F-15.
I'm at a loss.


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## silver_arrow_jetta (Jul 30, 2004)

wierd, isnt it? now my abs keep kicking it evry now and then. i am guessing it the ABS pump that is going


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## silver_arrow_jetta (Jul 30, 2004)

would it be air in the system?


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## DIAF (Sep 17, 2005)

That's a solid idea. I think mine started happening after I swapped out for stainless lines. 
I'll try re-bleeding again this weekend if the schedule and weather cooperate. 
The problem is that it's so hard to reproduce.
I'm shocked that we've stumped a technical forum!


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## silver_arrow_jetta (Jul 30, 2004)

i might have to bleed my system too


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## 2002gtibluvr6 (Oct 5, 2002)

*Re: (uniblk)*

if you got a vagcom code indicating a fault in the abs, i can almost guarentee one of your wheel speed sensors is screwed up. do you have an abs light in your cluster?
im sure anyone who has had their car dyno'd knows what im talking about but if your front wheels are moving faster then the rears *in the case of a dyno the rears dont move at all while the front obviously are* you will get a flashing brake light and a beep... the trouble codes come from abs wheel speed sensors, and if you have one that isnt functioning properly your car will beep at you and your lights will flash.
what do you wanna bet thats your problem...but of course nobody else told you that, and im really suprised especailly after your said you haad a vagcom code pop up


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## silver_arrow_jetta (Jul 30, 2004)

i have scanned the car multiple times(vagcom) and never get any codes or cels. I dont have any abs or brakes lights on either. the brake light, as mentioned, flashes and beeps once in a while under hard braking and acceleration


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