New owner of 2003 RS6 C5 Saloon

4.2 V8 40v biturbo - 450 bhp
4.2 V8 40v biturbo - 480 bhp (plus)
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Shoppinit
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Re: New owner of 2003 RS6 C5 Saloon

Post by Shoppinit » Wed Jul 14, 2021 7:12 pm

There are 2 circuits in the BLS. Brake lights coming on doesn’t necessarily mean both circuits are working.

Audi change the design of the BLS every six months. One of these days they’ll get it right.
Daytona RS6 C5 Avant. Viper'd, Billies, Waggers, MTM box brain, C6 stoppers, xcarlink, R8 coolant cap (woohoo)
///M3 E46 | XC90 (V8, natch) | Passat GTE
"The major difference between a thing that might go wrong and a thing that cannot possibly go wrong is that when a thing that cannot possibly go wrong goes wrong it usually turns out to be impossible to get at and repair."

HPsauce
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Re: New owner of 2003 RS6 C5 Saloon

Post by HPsauce » Wed Jul 14, 2021 7:48 pm

One circuit in the BLS goes to the ECUs the other to the brake lights VIA THE F125 SWITCH!
(The two operate a fraction of a millimetre apart as can be seen when monitoring via VCDS and pressing the pedal down VERY VERY slowly.)

And then there's the "Gear recognition signal" error which is also almost always an F125 issue.

So, the jury is out at present but if the problem is still there I'd be thinking F125 problem, possibly damage/debris inside it's a horrible mechanical device. :FIREdevil:

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norwichphoto
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Re: New owner of 2003 RS6 C5 Saloon

Post by norwichphoto » Wed Jul 14, 2021 8:38 pm

I noted it was a 4 terminal switch, just wasn’t sure whether it was a two circuit switch or something more complicated still. Anyway, no warning light yet, and an easy fit.
2003 Audi RS6 C5 Saloon in Avus Silver, with black leather upholstery (wife approves)
1998 TVR Chimaera 400 in Blaze Yellow, with green and biscuit leather upholstery (for sale, wife disapproves)
1993 Toyota Sera in Poppy Red, with standard cloth interior (daily driver)
1977 Lancia Montecarlo Evoluzione track car. (wife approves)

HPsauce
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Re: New owner of 2003 RS6 C5 Saloon

Post by HPsauce » Wed Jul 14, 2021 9:12 pm

If you take one apart (surprisingly easy) it's two totally separate circuits.
One just carries a very small current to signal to the ECUs, the other takes the full current to power the brake lights so can easily get burnt/corroded.
There's no relay on the brake lights, it's a direct circuit.

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chunky79
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Re: New owner of 2003 RS6 C5 Saloon

Post by chunky79 » Fri Jul 16, 2021 8:35 am

An even better reason to fit led brake light bulbs.
previous- 205 gti, 306 gti, 309 gtiGoodwood, S3, S4 V8 avant.
Gone but NEVER forgotten - C5 RS6 Misano red avant.

Now - PORK

If you don't know where you're going, any road will take you there!

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norwichphoto
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Re: New owner of 2003 RS6 C5 Saloon

Post by norwichphoto » Thu Jul 22, 2021 1:23 pm

New boot gas struts arrived as they were not doing much - they hadn't totally failed but were not really supporting the weight of the bootlid. Easy to replace , just need a narrow screwdriver to prise the spring clip out of its locking position. New Struts 4B5 827 552G. Came in Febi bags but they were marked Stabilus as per originals. Bought from Ebay £ 28.99 per pair.

Radio removal keys and parking chime also arrived but as its more dismantling will leave that until the next free weekend.
2003 Audi RS6 C5 Saloon in Avus Silver, with black leather upholstery (wife approves)
1998 TVR Chimaera 400 in Blaze Yellow, with green and biscuit leather upholstery (for sale, wife disapproves)
1993 Toyota Sera in Poppy Red, with standard cloth interior (daily driver)
1977 Lancia Montecarlo Evoluzione track car. (wife approves)

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Shoppinit
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Re: New owner of 2003 RS6 C5 Saloon

Post by Shoppinit » Thu Jul 22, 2021 3:14 pm

Yeah, my tailgate has struts failed from lack of use. It’s unbelievably heavy without assistance.
Daytona RS6 C5 Avant. Viper'd, Billies, Waggers, MTM box brain, C6 stoppers, xcarlink, R8 coolant cap (woohoo)
///M3 E46 | XC90 (V8, natch) | Passat GTE
"The major difference between a thing that might go wrong and a thing that cannot possibly go wrong is that when a thing that cannot possibly go wrong goes wrong it usually turns out to be impossible to get at and repair."

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Weiß-sechs
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Re: New owner of 2003 RS6 C5 Saloon

Post by Weiß-sechs » Fri Jul 23, 2021 1:18 pm

Recently replaced the bonnet strut. Failed from too much use...

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Shoppinit
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Re: New owner of 2003 RS6 C5 Saloon

Post by Shoppinit » Fri Jul 23, 2021 5:17 pm

Lol
Daytona RS6 C5 Avant. Viper'd, Billies, Waggers, MTM box brain, C6 stoppers, xcarlink, R8 coolant cap (woohoo)
///M3 E46 | XC90 (V8, natch) | Passat GTE
"The major difference between a thing that might go wrong and a thing that cannot possibly go wrong is that when a thing that cannot possibly go wrong goes wrong it usually turns out to be impossible to get at and repair."

steve2003rs6
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Re: New owner of 2003 RS6 C5 Saloon

Post by steve2003rs6 » Fri Jul 23, 2021 6:08 pm

Weib -Sechs yes indeed.
I had Better check my bonnet strut as well ?

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