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D2 - Interior Electrics Airbags, Sensors, climate modules, instrument clusters, switches etc

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  #1  
Old 3rd August 2013, 06:36 PM
RallyQuattro RallyQuattro is offline
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Default Speed signal from abs or cruise control? to my RS8 biturbo ecu

I have an Audi S8 -97 manual with RS6 engine but I have a fault code (16885) in the RS6 ecu that it is missing a speed signal.

So were can I find a speed signal in Audi A8/S8 94-99 ?

The cruise control must have this? but i don't know cable colour or where I can find this cable in my car?

Maybe also the ABS or clima have a speed signal?

And perhaps it is an speed signal output on the instrument cluster does anyone know this?
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Old 4th August 2013, 05:55 PM
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Conan_the_Librarian Conan_the_Librarian is offline
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There are a couple of speed signals input to the ecu. Abs Sensors at each wheel and output shaft on the transmission. There are also a couple of engine speed signals, input shaft, cam position and fly wheel hall sender. The ecu uses all of the for different functions.
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1996 4.2 A8SQ - Ming Blue. 178k on a cambelt! Trader's 8. Delivered to A8Parts at Lifex.
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  #3  
Old 5th August 2013, 08:29 AM
RallyQuattro RallyQuattro is offline
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But the question is where are these cables in my car?

My cruise control does not work anymore because it's electricity gas throttle on the RS6 engine so therefore I can take the cable that goes to the cruise control and link it to my RS6 ecu,
but where can I find the ecu to the cruise control and which cable is what I should be looking for?

Anyone have a diagram of the wires to the cruise control ecu ?
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Owns at the moment:
S8-97 biturbo = RS8 My new trackday car
A8-94, A8-96, A6 1.8tq -2004
2 Urquattro 20v-90 one red, one blue,
and one old Urquattro ex rallycar,

and some other cars..



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  #4  
Old 5th August 2013, 08:35 AM
HPsauce HPsauce is offline
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The cruise control in that era S8 is a separate module which I presume operates a servo (vacuum driven?) of some sort as the throttle pedal physically moves. It is optional.

Later models are fly-by-wire and the cruise function is integrated into the engine ECU so you "just" need to add the stalk/switches.
What vintage of engine ECU are you using and is it designed to work with a separate servo cruise control, or are you trying to bypass that?
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2016 Volvo V40 T5 Cross Country (4WD) with ALL the toys including adaptive cruise etc. etc. Osmium Grey with Blonde/Charcoal leather interior. Polestar performance "optimisation". (Even rarer than a D2 S8!) Oh, and a brand new engine at just under 30,000 miles on the factory one!
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1998 (very early) Ford Focus 1.8 Zetec; ABS/TCS, Heated screen/mirrors, Aircon. Added Auto-dim mirror, Leather seats, Trip computer, Cruise control, OEM Ford SatNav with CD changer.
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Old 5th August 2013, 08:43 AM
RallyQuattro RallyQuattro is offline
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I don't want my cruisecontrol to work!

I only wan't to get a (km/h and mph) speed signal from any cable in my Audi S8-97

I have an RS6 BCY engine with RS6 ecu and this ecu is missing a speed signal = I have a fault code (16885=speed signal) in the RS6 ecu and my tuning company that will remap it for 500hp+ want me first to fix this cable to my ecu so I get rid of this fault code..
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Owns at the moment:
S8-97 biturbo = RS8 My new trackday car
A8-94, A8-96, A6 1.8tq -2004
2 Urquattro 20v-90 one red, one blue,
and one old Urquattro ex rallycar,

and some other cars..



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  #6  
Old 5th August 2013, 09:51 AM
ainarssems ainarssems is offline
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Vehicle speed reading on 1997 8 is generated from speed sensor on gearbox output and processed in instrument cluster which then passes processed speed signal to ECU, ABS, cruise control, gearbox, radio, climate control, servotronic steering, satnav , ect.
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