FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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Main Unit Inputs, Ouputs, Bus, Power Supply




Main Unit Inputs







- Power supply +15 (20)
- Power supply +30 (1)
- Ground (G34P/G33P)
- Telephone mute (375)
- Telephone line input ± (375)

Main Unit Inputs, Bus


Control Module Inputs, Bus:






- Ignition +B (on/off) from DICE (628)
- Steering wheel controls from SID (541)
- Key Correct from TWICE (632)
- Diagnostics communication, see Bus and diagnostics communication.
See Powertrain Management/Computers and Control Systems/Information Bus/Description and Operation/Bus Diagnosis.

Main Unit Ouputs







- Mute control, external amplifier (354)
- Line output, external amplifier, right/left channel ± (354)
- Loudspeaker, right/left channel ±, front/rear (266)

Main Unit - I


Main Unit:






The main unit for the telephone system is the audio system main unit. It is connected to the wiring harness and bus via 3 connectors (A, B, C) and an 8-pin DIN connector (for external amplifier).

The task of the main unit in the telephone system is as follows:
- Disconnect normal sound from selected source during a call This is achieved by sending a mute signal to the main unit, which then disconnects the normal sound from the loudspeakers and the signal to the external amplifier if fitted.

To receive an audio signal (line input) from the telephone (incoming sound) via the telephone connector and reproduce it via the audio system speakers.

See Test readings, control module connections.

Main Unit Power Supply

Main unit power supply:











Power supply +15
From fuse 24 to the main unit, pin 4(A).

Power supply +30
From fuse 13 to the main unit, pin 7(A).

Main Unit - II


Main Unit:






The main unit for the telephone system is the audio system main unit. It is connected to the wiring harness and bus via 3 connectors (A, B, C) and an 8-pin DIN connector (for external amplifier).

The task of the main unit in the telephone system is as follows:
- Disconnect normal sound from selected source during a call. This is achieved by sending a mute signal to the main unit, which then disconnects the normal sound from the loudspeakers and the signal to the external amplifier if fitted.

To receive an audio signal (line input) from the telephone (incoming sound) via the telephone connector and reproduce it via the audio system speakers.

See Test readings, control module connections.

Main Unit Ouputs, Bus


Control Module Inputs, Bus:






- Sound (acoustic information) used by SID (541)
- Text message (text information for main unit) used by SID (541)
- Diagnostics communication, see Bus and diagnostics communication.
See Powertrain Management/Computers and Control Systems/Information Bus/Description and Operation/Bus Diagnostics.