Steering wheel controls
Steering wheel controls |
General |
The audio system can also be operated with the steering wheel controls (control buttons on the steering wheel). The steering wheel controls consist of 2 units (6 buttons). Detailed instructions on their use is given in the Owner's Manual.
The steering wheel controls are connected to the SID unit and provide information on which switches are activated. The SID unit then sends the current button information to the bus, which is read by the main unit.
Function |
The SID unit supplies the steering wheel controls with +5V via pin 3 and grounds through pin 18.
The 6 switches on the steering wheel consist of 6 resistors connected in series. When a button is pressed, the switch concerned is grounded, se the table.
Depending on which button is pressed, the aggregate resistance in the circuit varies and with it the voltage detected by the SID unit.
Diagnostics |
On open-circuit/short to B+ and short-circuit to ground for more than 5 minutes, the SID generates diagnostic trouble code B2371.
Button
|
Function
|
Voltage (V) / Resistance (ohms)
|
VOL -
|
Reduce volume
|
0.7/82
|
VOL +
|
Increase volume
|
1.2/164
|
SRC
|
Select radio/tape/CD
|
1.8/284
|
SEEK >>
|
Search forwards
|
2.4/464
|
<< SEEK
|
Search backwards
|
3.0/794
|
NXT
|
Preset radio setting/tape side/
CD disc |
3.6/1474
|