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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