8. CU Assembly and Startup
8.5.
Replacement of a CU3 control unit
All CU41 variants can substitute a CU3 control unit without
changing the signal routing. When replacing the CU3, the larger
dimensions of the CU4 control unit must, however, be considered.
If a CU43 is to replace a CU33 control unit, the change of the seat
lifting signals must be observed.
The following table shows the details.
AS-interface
output data bit
CU33
CU43
DO0
main valve
main valve
DO1
lower seat lifting
upper seat lifting
DO2
upper seat lifting
lower seat lifting
In order to prevent the activation of the wrong seat lift after CU
replacement, the following adaptions can be carried out:
- Change in the control software. – or -
- The interchange of the electrical connections of the pneumatic
valves 2 and 3 at the electronic module of CU43. In this case, the
signals of CU43 as well as of CU33 can be controlled.
The air hoses leading to the actuators must not be exchanged.
For the lower seat lift, the CU is equipped with a separate exhaust
air channel due to the larger volume of the actuator. A mix-up of the
air hoses can lead to disruption in operation.
APV_CU4 AS-i_UK-5_072018.indd
UK
Control Unit
CU4 AS-interface
Instruction manual: UK - rev. 5
APV
39