Chevrolet Silverado / GMC Sierra. Manual — part 2228

3. Inspect that the ground straps between the engine and the frame are clean and tight.

4. If the noise is still present, inspect the charging system for proper operation.

5. Install a filter GM P/N 1224205 in the battery voltage feed circuit to the radio.

6. If the noise is not eliminated, install the filter in each following variation:

Install the filter with the single wire side toward the radio and the ground wire
attached to chassis ground.

Remove the ground to the filter.

Reverse the filter so the 2-wire side is toward the radio with the ground wire attached
to chassis ground.

Remove the ground from the filter.

7. If the filter GM P/N 1224205 causes a delay when turning the radio ON or OFF, or other

problems, remove the filter and install a 0.47 micro farad capacitor to chassis ground.

8. Before reassembling the vehicle, remove any unneeded filters.

9. Test the functionality all of the vehicle systems for proper operation and function.

VIDEO ENTERTAINMENT SYSTEM TROUBLESHOOTING HINTS

Schematic Reference: Video System Schematics

Many conditions that affect video system operation may be corrected without removing the
radio, the digital video disc (DVD) player or the video entertainment overhead console
from the vehicle. Make sure to understand all features of system operation before beginning
the diagnosis of the system. Verify the condition and follow the diagnostic procedures in
order to isolate and correct the condition.

Be sure the vehicle battery is fully charged before beginning video entertainment system
diagnosis.

Video or Audio Distortion

The manufacturing process for producing DVDs does not have the same quality control processes
in place that compact disk manufacturing does. If there are video or audio quality problems with
an individual DVD, try playing that disk in another DVD player. If the quality is poor for both
players, return the disk to the place of purchase and request an exchange. If the quality problem is
only seen in one of the players, examine the disk for scratches dirt or smudges and attempt to
clean the disk with one of the disk cleaning systems that are commercially available.

Video or audio distortion during auxiliary playback can often be attributed to the DC to AC
inverter that is used to power the auxiliary device. The power inverters tend to introduce noisy

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signals into the vehicle electrical system.

Video Entertainment System Wireless Headphone Inoperative

1. Volume control on the wireless headphone set is turned all the way down. Adjust the

volume control on the headphones.

2. Dead batteries in the wireless headphone set. Turn on power to the headphone set. If the

headset indicator does not turn on, replace the batteries in the headset as needed.

3. Faulty headphone set. Test the operation of the system using a known good headphone set. If

operation is OK, replace the vehicle headphone set.

Video Entertainment System Remote Control Inoperative

The buttons on the video remote control do not operate the video disc player but the buttons on
the video disc player operate normally.

1. Dead batteries in the video remote control. Replace the dead batteries.

2. Faulty remote control. Test the operation of the system using a known good remote control.

If operation is OK, replace the remote control.

Discs Will Not Eject

1. Attempt to remove the CDs/DVDs from the radio by pushing the "Eject" button on the

radio. If there is a "chatter" noise, go to step two. If there is no chatter noise and the discs
will not eject from the radio, send the radio to your authorized Electronic Service Center
for repair.

2. Remove the radio from the Instrument Panel of the vehicle but do not remove the electrical

connectors. Refer to Radio Replacement (without RPO SLT) or Radio Replacement
(with RPO SLT).

3. Some versions of these radios have a 9.5 mm x 13 mm oval hole on the top cover of the

radio, near the back of the case. If the radio being serviced has this hole, proceed to step
four. Otherwise the radio will need to be returned to your authorized Electronic Service

IMPORTANT: The following information lists the most probable cause of the

concern to the least probable cause followed by the appropriate
test for that condition.

IMPORTANT: The following information lists the most probable cause of the

concern to the least probable cause followed by the appropriate
test for that condition.

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Center for repair.

4. Push the "Eject" button. While the discs are attempting to eject, insert a plastic pen cap, or

similar plastic object into the hole to assist the top disc out of the radio.

5. After the top disc is removed, push the "Eject" button again to remove the bottom disc.

6. Check the operation of the radio to see if a CD or DVD can be inserted and then ejected. If

a CD or DVD can be inserted and ejected from the radio, then reinstall the radio into the
Instrument Panel. If a CD or DVD cannot be inserted and then ejected from the radio, send
the radio to your authorized Electronic Service Center for repair.

DIGITAL RADIO MALFUNCTION

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 provides an overview of each diagnostic category.

Diagnostic Fault Information

Circuit/System Description

The digital radio receiver (DRR) receives an XM satellite radio signal via the cellular and digital
radio antenna. This signal is passed to the DRR through the digital radio antenna coax. From the
DRR, separate left and right audio signals (+ and -) are sent to the radio. The radio then processes
these signals and passes the audio to the appropriate speakers or amplifier.

Reference Information

Schematic Reference

Circuit

Short to

Ground

Open/High

Resistance

Short to

Voltage

Signal

Performance

Left Audio Signal (+)

1

1

1

-

Left Audio Signal (-)

1

1

1

-

Right Audio Signal (+)

2

2

2

-

Right Audio Signal (-)

2

2

2

-

Digital Radio Antenna Coax

3

3

3

-

1. No or distorted audio from left side speakers when listening to digital radio
2. No or distorted audio from right side speakers when listening to digital radio
3. Poor or no digital radio reception

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Radio/Navigation System Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Radio/Audio System Description and Operation

Electrical Information Reference

Circuit Testing

Connector Repairs

Testing for Intermittent Conditions and Poor Connections

Wiring Repairs

Scan Tool Reference

Control Module References for scan tool information

Special Tools

EL-48028 Digital Radio Test Antenna. See Special Tools.

Circuit/System Verification

1. Tune to a strong AM or FM station and verify each speaker is producing clear and even

sound, with no distortion.

If any speaker is not producing sound or the sound produced is distorted, refer to
Speaker Malfunction.

2. With the vehicle outside in an area with an unobstructed view of the southern sky, tune to

XM. Verify XM reception is clear and the No XM Signal message is not displayed on the
radio.

If the No XM Signal message is displayed or XM reception is poor, refer to Digital
Radio Antenna Circuit Malfunction.

3. Radio tuned to XM, use the radio balance function to transfer audio between the left and

right side of the vehicle. Verify clear and even sound is heard from each side of the vehicle.

If either side of the vehicle is not producing sound or the sound produced is distorted,

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