ABS brake system components and fitting locations — AUDI

Audi
Audi Q7
2007
Running gear
Brake system
Edition
03.2013
ABS brake system components and fitting locations
ESP and TCS warning lamp (for electronic stabilisation and traction control)
K155
Location: in instrument cluster
Flashes when the vehicle is in motion and the ESP control is in operation
Lights up when the ignition is switched on (function check) and goes out after the vehicle has been in motion for a short time
Lights up if there is a malfunction in the ESP
Lights up if there is a malfunction in the ABS, since the ESP works in conjunction with the ABS
Lights up when the ESP is switched off
Lights up during automatic self-adaption of the sensor systems and goes out after the vehicle has been in motion for a short time
when the battery has been disconnected and then re-connected
when the vehicle has been jump-started
when the battery charge level is very low
If the warning lamp lights up after the engine is started, the system may have been cut off automatically. In this case, the ESP can be re-activated by switching the ignition off and back on again.
ABS warning lamp
K47
Location: in instrument cluster
Lights up for a few seconds when the ignition is switched on and goes out after the automatic ABS self-test has been completed, providing no faults have been detected
The following conditions indicate a malfunction of the ABS:
ABS warning lamp does not light up when ignition is switched on
Warning lamp does not go out again after a few seconds.
Warning lamp lights up while vehicle is in motion
If a malfunction should occur, the vehicle can still be braked in the normal way without the ABS function
The ESP warning lamp lights up in addition to the ABS warning lamp if there is a malfunction in the ABS
WARNING
If the ABS warning lamp and the brake system warning lamp light up there is a risk that the rear wheels may lock up earlier under braking.
Brake system warning lamp
K118
Location: in instrument cluster
Flashes if there is a malfunction in the brake system
Flashes if there is a malfunction in the ABS
Flashes if the brake fluid level is too low
ABS hydraulic unit
N55
with
ABS control unit
J104
With integrated brake pressure sender
Note
The brake pressure sender in control unit J104 cannot be renewed separately.
There is no provision for separating the hydraulic unit
a
and the control unit
b
Location: in plenum chamber (right-side) below engine control unit
Switch off ignition before detaching connector
Removing and installing
Chapter
Vacuum pump for brakes
V192
The vacuum pump is not fitted in conjunction with all engine and gearbox versions
Location: in engine compartment (front right)
There is no provision for servicing the vacuum pump. The pump must be renewed if defective.
Removing and installing
Chapter
Note
Any faults occurring in the vacuum pump are stored in the fault memory of the engine control unit
Brake servo pressure sensor
G294
The vacuum pump is not fitted in conjunction with all engine and gearbox versions
Location: In vacuum hose to brake servo
Removing and installing
Chapter
Brake servo
Removing and installing
Chapter
Brake master cylinder
Removing and installing
Chapter
Brake light switch
F
and
brake pedal switch
F47
Removing and installing
Chapter
Location: on brake pedal
ESP sensor unit
G419
Combined
lateral acceleration sender
G200
,
yaw rate sender
G202
and
longitudinal acceleration sender
G251
Location: Under centre console
Removing and installing
Chapter
Steering angle sender
G85
Location: On steering column between steering wheel and steering column switch
Observe installation instructions
Chapter
TCS (ASR)/ESP button
E256
Fitting location: in centre console
Front right speed sensor
G45
/
front left speed sensor
G47
Renewing
Chapter
Front wheel bearing and hub unit (left/right)
The ABS sensor ring is installed in the wheel bearing
Rear right speed sensor
G44
/
rear left speed sensor
G46
Renewing
Chapter
Rear wheel bearing and hub unit (left/right)
The ABS sensor ring is installed in the wheel bearing
Diagnostic connection
Fitting location: behind cover in driver's footwell
Fig.
Foot-operated parking brake
Removing and installing
Chapter
Diagnostic connection