light AUDI A4 1995 B5 / 1.G Brakes Description Of Systems Workshop Manual

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EBD

Electronic Brake Distribution
Specialized software stored in the ABS control
module -J104-, called Electronic Brake
Distribution (EBD), assumes the function of the
brake pressure regulator.
The signal sent to the instrument cluster when
ABS fails is pulsed if the EBD function remains
operational in emergency mode. The instrument
cluster distinguishes between no signal, a pulsed
signal, and a steady signal. The ABS/EDL
indicator lamp and the red symbol for "Brake
system malfunction" will light up accordingly.
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1 - Terminal 15
2 - Signal for controlling the ABS/EDL indicator lamp and the red "brake
system malfunction" symbol.
3 - Voltage supply for the ABS/EDL indicator lamp.
4 - Voltage supply for the red "brake system malfunction" symbol.
A - In interval "A" (with "ignition on") a self-test of the ABS/EDL indicator
lamp is carry outed for two seconds using signal "2" (lamp lights up).
During this interval, the instrument cluster suppresses the red "brake
system malfunction" symbol.
B - Signal "2" is not available in interval "B". The ABS/EDL indicator lamp
and the red "brake system malfunction" symbol do not light.
C - In interval "C", the On Board Diagnostic recognized a DTC, which did
not deactivate the EBD. Signal "2" is pulsed. Only the ABS/EDL indicator
lamp comes on.
D - In interval "D", the On Board Diagnostic recognized a DTC, which did
deactivate the EBD. Signal "2" is steady. Both the ABS/EDL indicator
lamp and the red "brake system malfunction" symbol light up.
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ASR prevents the wheels being powered from
spinning during acceleration by reducing engine
load. It is active throughout the entire speed
range. The EDL and ASR functions work in
combination during vehicle acceleration.
ASR can be switched on and off by pressing the
traction control button in the center of the center
console. ASR is re-activated on its own when the
ignition is switched on. When the traction control
button is operated, the ASR indicator lamp lights
up in the instrument cluster. During adjustment
mode, the indicator lamp blinks three times per
second.
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ESP

Electronic Stabilization Program (ESP)
The Electronic Stabilization Program (ESP) is a
driving dynamics regulation system. It stabilizes
the vehicle both in understeer and oversteer
situations. ESP regulation includes the functions
of EBD, ABS, EDL and ASR. A special function
of ESP is that it can brake individual wheels.

ESP includes the functions of EBD, ABS, EDL
and ASR. The individual components have
the following functions:
The ASR and ESP functions can be switched on
and off using the ASR/ESP switch on the center
console. If the driver steps on the brake pedal,
the status of the ESP switch is ignored. When
braking, ESP is always active. When the ignition
is switched on, the ASR and ESP functions are
activated.
When switched off, the ASR/ESP indicator light
is lit up in the instrument cluster. During
adjustment mode, the indicator lamp blinks three
times per second.
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