Test Description
The numbers below refer to the step numbers on the diagnostic table.
2.Lack of communication may be due to a partial malfunction of the class 2 serial data circuit or due to a total malfunction of the class 2 serial data circuit. The specified procedure will determine the particular condition.
4.The symptom list in Symptoms will determine the correct diagnostic procedure to use.
5.The presence of DTCs which begin with "U" indicate some other module is not communicating. The specified procedure will compile all the available information before tests are performed.
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The numbers below refer to the step numbers on the diagnostic table.
2.Clear all DTCs and cycle the ignition to verify that the DTC did not falsely set.
3.Clear all DTCs after the repair procedure is complete.
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The numbers below refer to the step numbers on the diagnostic table.
2.This step verifies that the DTC is still present.
3.This step isolates the fault condition.
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The number below refers to the step number on the diagnostic table.
3.Due to current limiting capabilities in the module, an antenna cable shorted to ground could still show 1200-1800 mV.
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The numbers below refer to the step numbers on the diagnostic table.
2.After clearing the DTCs and theft information, the radio relearns the VIN upon cycling the ignition switch.
3.After completing the repair procedure, clear all DTCs.
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Symptoms - Entertainment
| IMPORTANT | The following steps must be completed before using the symptom tables. |
- Perform «DIAGNOSTIC SYSTEM CHECK - RADIO/AUDIO SYSTEM»(ref-189107-S26275507032005090700000) before using the Symptom Tables in order to verify that all of the following conditions are true: There are no DTCs set. The control module(s) can communicate via the serial data link.
- Review the system operation in order to familiarize yourself with the system functions. Refer to «RADIO/AUDIO SYSTEM DESCRIPTION AND OPERATION»(ref-189107-S02229053262005090700000) .
Radio/Audio System Description and Operation
Battery positive voltage is provided to the radio from the RDO/INTLP/ONSTAR fuse in the fuse block- I/P. The radio is grounded to G302 and G303. The radio is enabled/disabled by class 2 messages from the body control module (BCM).
The Entertainment System on this vehicle is configured with a base and uplevel system. The base and uplevel systems contain a radio, antenna, speakers, and on some vehicle lines an audio amplifier.
The uplevel system differs from the base system by providing the customer with enhanced audio system features. Some of those features may include the radio data system (RDS), an audio amplifier and programmable equalizer (EQ). Satellite digital radio (U2K) is available with uplevel systems.
The following list shows the radios available for this vehicle
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- Base Radio (UM7) - AM/FM Stereo
- Base Radio (UM6) - AM/FM Stereo and Cassette
- Base Radio (U1C) - AM/FM Stereo and CD
- Uplevel Radio (UP0) - AM/FM Stereo, Cassette, CD, and RDS
- Uplevel Radio (U1P) - AM/FM Stereo, CD, EQ and RDS
- Uplevel Radio (U1Q) - AM/FM Stereo, Cassette, CD, EQ and RDS
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Each item in the list below represents topics covered in detail below
- AM/FM Reception
- XM Reception
- Antenna
- Audio Amplifier
- Theft Deterrent
- Remote Playback Device
- Radio Data System (RDS)
- XM Satellite Radio
- XM Advisory Messages
- Radio Chime Level Adjustment
- Tape/CD Player Error Messages