Audi TT (2007 year). Manual - part 272

Protected by copyright. Copying for private or commercial purposes, in part or in whole, is not 
 permitted unless authorised by AUDI AG. AUDI AG does not guarantee or accept any liability 
     with respect to the correctness of information in this document. Copyright by AUDI AG.

33

ABS control unit J104

–   Road speed signal

Control unit with display in dash panel 
insert J285

–   Ambient temperature

Driver door control unit J386
Front passenger door control unit J387

–   Door glass position

Convenience system central control unit 
J393

–   Requirements for convenience opening/

closing

Steering column electronics control unit 
J527

–   Status of terminal 15

Climatronic control unit J255

–   Transition from closed loop to open loop 

control

–   Heated rear window button E230 

Disable function

CAN data bus interfaces

The overview shows by way of example the 
information exchanged across the CAN data bus.
The individual control units send or receive data 
required for smooth operation of the convertible 
top.

Onboard power supply control unit J519

–   Rear window defroster on or off

Convertible top operation
control unit J256

–   Convertible top closed and locked

–   Convertible top in intermediate 

position

–   Convertible top stowed and locked

–   Power window regulator 

Command to lower the door glasses
Command to close the door glasses

–   Messages in the centre display

of the dash panel insert

–   Convertible top status, activation 

of the convertible top operation 
warning lamp

Sleep standby

Digital sound package control unit J525

–   Sound tuning for convertible top open/

closed

Protected by copyright. Copying for private or commercial purposes, in part or in whole, is not 
 permitted unless authorised by AUDI AG. AUDI AG does not guarantee or accept any liability 
     with respect to the correctness of information in this document. Copyright by AUDI AG.

34

Electrical convertible top control system

Function diagram

Protected by copyright. Copying for private or commercial purposes, in part or in whole, is not 
 permitted unless authorised by AUDI AG. AUDI AG does not guarantee or accept any liability 
     with respect to the correctness of information in this document. Copyright by AUDI AG.

35

391_003

Legend:

E137  Convertible top switch

F170

Convertible top right latch switch

F171

Convertible top stowed switch

F172

Convertible top front latch switch

F202  Convertible top front switch
F294

Convertible top lock open switch

F295

2x convertible top lock closed switch
(left/right)

G596 Left convertible top cover sender
G597 Right convertible top cover sender

J256

Convertible top operation control unit

J393

Convenience system central control unit

J519

Onboard power supply control unit

L72

Convertible top operating switch illumination

V118

Convertible top operation hydraulic pump

V223

Convertible top lock motor

V381

Right convertible top cover motor

V383

Left convertible top cover motor

Z1

Heated rear window

Convenience CAN bus (high)

Convenience CAN bus (low)

Terminal 58s

to J393 (manual convertible top only)

*

Hall sensors are used with the automatic
convertible top

**

a microswitch is used with the manual 
convertible top

4

3

2

1

Protected by copyright. Copying for private or commercial purposes, in part or in whole, is not 
 permitted unless authorised by AUDI AG. AUDI AG does not guarantee or accept any liability 
     with respect to the correctness of information in this document. Copyright by AUDI AG.

36

391_087

3

3

2

1

4

4

6

6

5

7

7

8

Hydraulics

Hydraulic system

Convertible top opening cycle

The hydraulic system comprises an electric motor, a 
pump housing and the oil tank which are connected 
to the hydraulic cylinders by plastic sheathed lines.
The convertible top is opened or closed by reversing 
the direction of rotation of the electric motor. When 
the convertible top switch is actuated, the hydraulic 
pump turns clockwise. The two-way valve closes the 
return line on the pressure side and simultaneously 
opens the pressureless return line on the opposite 
side. A slight excess pressure is applied to the check 
valve by increasing the pressure. The hydraulic 
pressure flows into the hydraulic cylinder above the 
piston rod and pushes it down, opening the 
convertible top.
At the same time, pilot pressure is applied to the 
pressure-controlled check valve on the pressureless 
side through a bypass port from the pressure side.

Oil pressure side

Oil return line

Control pressure

5 Emergency 

release

6 

Return flow restrictors

7 Hydraulic 

cylinder

8

Oil filter in the hydraulic pump

Legend:

1 

Electric motor with hydraulic pump

2 Two-way 

valve

3 

Spring-loaded pressure relief valve

4 

Pressure-controlled check valve

This causes the pressure relief valve to open and the 
hydraulic fluid displaced backwards by the cylinder 
flows to the pump or back into the oil pan. 
If the dead centre position of the convertible top 
kinematics is exceeded, restrictor orifices create a 
backpressure which prevents the convertible top 
from lowering too quickly. 
If the convertible top switch is still being actuated 
when the convertible top reaches its end position, 
the hydraulic pressure continues rising to a 
maximum of approx. 160 bar. A spring loaded valve 
opens and the excess hydraulic pressure flows back 
into the oil tank.
When the convertible top switch is released, the 
check valve closes and a residual pressure in the 
cylinder stabilises the convertible top linkage while 
driving.

Oil intake side

Spring-loaded valve 
is open on reaching 
the max. pressure of 
approx. 160 bar