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Chevrolet Silverado / GMC Sierra. Manual - part 2219
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Testing
Ignition ON, with a scan tool, clear all DTCs and operate the audio system within the Conditions
for Running the DTC.
If the DTC resets, replace the audio amplifier.
Repair Procedures
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
Control Module References for audio amplifier replacement, setup, and programming
DTC B1025, B1035, B1045, OR B1055
Diagnostic Instructions
Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
Review Strategy Based Diagnosis for an overview of the diagnostic approach.
Diagnostic Procedure Instructions provide an overview of each diagnostic category.
DTC Descriptors
DTC B1025 01
Audio Output 1 Left Front Circuit Short to Battery
DTC B1025 02
Audio Output 1 Left Front Circuit Short to Ground
DTC B1025 04
Audio Output 1 Left Front Circuit Open
DTC B1035 01
Audio Output 2 Right Front Circuit Short to Battery
2008 Chevrolet Silverado 1500
2008 ACCESSORIES & EQUIPMENT Cellular, Entertainment, and Navigation - Cab & Chassis Sierra, Cab & Chassis
Silverado, Sierra & Silverado
DTC B1035 02
Audio Output 2 Right Front Circuit Short to Ground
DTC B1035 04
Audio Output 2 Right Front Circuit Open
DTC B1045 01
Audio Output 3 Left Rear Circuit Short to Battery
DTC B1045 02
Audio Output 3 Left Rear Circuit Short to Ground
DTC B1045 04
Audio Output 3 Left Rear Circuit Open
DTC B1055 01
Audio Output 4 Right Rear Circuit Short to Battery
DTC B1055 02
Audio Output 4 Right Rear Circuit Short to Ground
DTC B1055 04
Audio Output 4 Right Rear Circuit Open
Diagnostic Fault Information
Circuit
Short to
Ground
Open/High
Resistance
Short to
Voltage
Signal
Performance
Left Front Speaker Signal
Circuits (Front Door and
Tweeter)
B1025 02
B1025 04
B1025 01
-
Right Front Speaker Signal
Circuits (Front Door and
B1035 02
B1035 04
B1035 01
-
2008 Chevrolet Silverado 1500
2008 ACCESSORIES & EQUIPMENT Cellular, Entertainment, and Navigation - Cab & Chassis Sierra, Cab & Chassis
Silverado, Sierra & Silverado
Circuit/System Description
The up-level radio (UQA) supplies 4 channels of audio to an amplifier.
Each of the audio output channel circuits (+) and (-), at the radio and at the amplifier (if
equipped) have a DC bias voltage that is one half of the battery voltage. When using a DMM,
each of the audio output channel circuits will measure approximately 6.5V DC. The audio being
played on the system is produced by a varying AC voltage that is centered around the DC bias
voltage on the same circuit. The AC voltage is what causes the speaker cone to move and produce
sound. This voltage will vary depending on what type of audio is being listened to, talk or music,
and type of music, as well as the volume setting of the system. Low volume and talk settings will
measure around 1V AC and less, where constant music may measure 3V AC and slightly higher.
In an amplified audio system, these similar AC voltage measurements may be slightly higher on
the output of the amplifier, and the typical AC voltage readings at the output of the radio are less
than 1V AC.
Conditions for Running the DTC
The radio is ON.
Conditions for Setting the DTC
Set by Radio
The radio sets a current status for this DTC when a short to ground, short to voltage or an open is
detected on any of the 4 speaker channel outputs from the radio.
Set by Bose Amplifier
The DTC will not set during normal amplifier operation. The vehicle must have the ignition OFF
for several hours and the fault must be present during amplifier power-up.
DTC B1025 01, B1035 01, B1045 01, B1055 01
A short to voltage is detected on the specified (+) or (-) signal circuit
DTC B1025 02, B1035 02, B1045 02, B1055 02
Tweeter)
Left Rear Speaker Signal
Circuits (Rear Door)
B1045 02
B1045 04
B1045 01
-
Right Rear Speaker Signal
Circuits (Rear Door)
B1055 02
B1055 04
B1055 01
-
2008 Chevrolet Silverado 1500
2008 ACCESSORIES & EQUIPMENT Cellular, Entertainment, and Navigation - Cab & Chassis Sierra, Cab & Chassis
Silverado, Sierra & Silverado
A short to ground is detected on the specified (+) or (-) signal circuit
DTC B1025 04, B1035 04, B1045 04, B1055 04
An open is detected on the specified (+) or (-) signal circuit
Action Taken When the DTC Sets
No sound is present from one or more of the speakers.
Conditions for Clearing the DTC
Set by Radio
The fault condition becomes history if not present for 0.25 seconds.
Set by Bose Amplifier
The fault condition becomes history after the vehicle ignition has been OFF for several hours and
then the ignition turns ON.
Diagnostic Aids
Speakers located in the front A-pillar are connected to the same channel as the speaker in the
door. A DTC will only set after the amplifier only on up-level radios.
Reference Information
Schematic Reference
Radio/Navigation System Schematics
Connector End View Reference
Component Connector End Views
Electrical Information Reference
Circuit Testing
Connector Repairs
Testing for Intermittent Conditions and Poor Connections
Wiring Repairs
2008 Chevrolet Silverado 1500
2008 ACCESSORIES & EQUIPMENT Cellular, Entertainment, and Navigation - Cab & Chassis Sierra, Cab & Chassis
Silverado, Sierra & Silverado
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