Brake lights only working if pressed super hard

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dirtygertie
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Brake lights only working if pressed super hard

Post by dirtygertie »

I've had a couple of instances where people (I know) who have followed me have told me that my brake lights aren't working; once checked at home they seemed fine.

checked again today after someone else bringing it to my attention and it seems that they only light up once the brakes are pressed hard.

has anyone got any ideas what may be causing this?
Karen x

We're in the stickiest situation since Sticky the Stick Insect got stuck on a sticky bun. -hmmmmm

1982 2l Aircooled with a name!

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kevtherev
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Re: Brake lights only working if pressed super hard

Post by kevtherev »

there's a little pressure switch in the master cyl, it may be calling it a day.
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dirtygertie
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Re: Brake lights only working if pressed super hard

Post by dirtygertie »

Thanks Kev, this was changed last year.......and thinking about it we have had intermittent problems since.

Will try changing it again - we might have a dodgy one
Karen x

We're in the stickiest situation since Sticky the Stick Insect got stuck on a sticky bun. -hmmmmm

1982 2l Aircooled with a name!

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Re: Brake lights only working if pressed super hard

Post by H-G »

Been there. New pressure switch in the master cylinder fixed it. 15 minute job but make sure to put a few rags under the switch when you swap them over to soak up and brake fluid that drips out.

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VWCamperfan
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Re: Brake lights only working if pressed super hard

Post by VWCamperfan »

It's not uncommon for some of these to go hard inside the switch. Means you have to put more pressure on to get a brake light, exactly what you have got! As Kev says, stick a new one in, should be fine.
Mark.

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dirtygertie
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Re: Brake lights only working if pressed super hard

Post by dirtygertie »

cheers guys
I forgot where I got the last one from.....can I get it from GSF?
Karen x

We're in the stickiest situation since Sticky the Stick Insect got stuck on a sticky bun. -hmmmmm

1982 2l Aircooled with a name!

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kevtherev
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Re: Brake lights only working if pressed super hard

Post by kevtherev »

yep or VW

part 113945515G (3pin)
Last edited by kevtherev on 31 Aug 2010, 19:59, edited 1 time in total.
AGG 2.0L 8V. (Golf GTi MkIII)

dirtygertie
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Re: Brake lights only working if pressed super hard

Post by dirtygertie »

kevtherev wrote:yep or VW
Karen x

We're in the stickiest situation since Sticky the Stick Insect got stuck on a sticky bun. -hmmmmm

1982 2l Aircooled with a name!

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kevtherev
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Re: Brake lights only working if pressed super hard

Post by kevtherev »

part 113945515G (3pin)
AGG 2.0L 8V. (Golf GTi MkIII)

langb20
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Re: Brake lights only working if pressed super hard

Post by langb20 »

I have this exact problem, '85 diesel bus... but, I also (mistakenly) purchased a 3 pin switch to only find two on the existing one. hmm, can i just piggy some wires to get the new one working or do I have to get a two-pin version from somewhere?
advice appreciated
Brent
'82 TDI project camper
'85 AAZ Panel daily drive

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Re: Brake lights only working if pressed super hard

Post by langb20 »

ok so been out to play, quick update
black/red wire is earth
yellow/red wire is power
the 2-pin switch i took off had a '13' on one pin, not sure which one was connected to this, whoops pulled it off too quickly without noticing.

I took the earth out of the connector block since if this fell off, it would only earth itself and that way the power stays protected in the plastic block connector

when swapping over the switches, I got some crud out as it was dripping away, gave a slight pump (downward only) of the brake pedal too, but not to let it back up as it would suck air in with the switch off. also gave the pipe off the top of the master cylinder a 'bleed' just in case there was some air up there.

all tightened up and back together, I put the wires on the two pins that face each other. no discernable improvement as yet, but it does work eventually as the pedal gets down. I usually drive only lightly on the brakes - travelling slowly, anticipating stops etc. but pedal needs to go down quite a lot to make contact still.

next port of call will be to clean up earth contacts, thanks in advance for any other advice
Brent
'82 TDI project camper
'85 AAZ Panel daily drive

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kevtherev
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Re: Brake lights only working if pressed super hard

Post by kevtherev »

you need this ..
VW Part No.. 113 945 515H two pin switch

GSF or VW would have these I would think
AGG 2.0L 8V. (Golf GTi MkIII)

langb20
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Re: Brake lights only working if pressed super hard

Post by langb20 »

roger that. thanks very much
'82 TDI project camper
'85 AAZ Panel daily drive

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