Entertainment System: Other Chevrolet SSR I

Intermittent

Faulty electrical connections or wiring may be the cause of intermittent conditions. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.

Identifying Concerns

1. In order to isolate the source of the noise/poor reception, identify the ignition switch position that the concern is most noticeable: Turn the ignition switch to the accessory position. Turn ON the radio. Seek up 88-108 FM then 550-1600 AM. Record the number of valid radio stations where the tuner stops. Repeat these steps with the ignition ON, and the engine OFF then again with the engine running.
2. Return the ignition switch to the position that the concern was most noticeable.
3. Remove fuses or circuit breakers one at a time until the noise has been eliminated.
4. Identify what systems or components are powered by the fuse.
5. Reinstall all fuses and circuit breakers.
6. Disconnect the components powered by the fuse one at a time until the concern has been eliminated.

Corrective Action

1. Inspect the ground integrity of the component or system causing the noise.
2. Malfunctioning and marginal components such as relays and solenoids may cause noise and/or poor reception.
3. Always use a braided ground strap when applying additional grounds and keep the ground strap as short as possible.
4. If the noise source is found to be coming from the vehicle harness: Route the antenna cable separately from the wire harness that is emitting the noise. Use aluminum or nickel tape in order to shield the antenna cable. Try variations of the following repairs: Try adding only aluminum or nickel tape before adding a ground strap to the tape. Wrap a ground strap 360 degrees around the tape, securing the other end of the strap to chassis ground.
5. Capacitors work best on switch pops and low frequency noise.
6. Filters work best on high frequency whines and static.
7. After adding any suppression device, inspect all of the vehicle systems including those not related to the audio system, for proper operation and function.
8. Whenever possible, make a test harness that includes filters or capacitors. Always inspect the effectiveness and operation before permanent installation.
9. If an audible pop is caused due to operating a switch, perform the following repairs as necessary: Add a capacitor across the contacts of the switch. Add a capacitor from the battery positive voltage (B+) side of the switch to chassis ground. Add a capacitor from the ground side of the switch to chassis ground.
10. Use the following available noise suppression devices: 220 micro farad (50 V) capacitor GM P/N 1227895 - Works well for ignition system related noise. 0.47 micro farad capacitor GM P/N 1227894 - Works well for switches and relays. Feed through capacitor GM P/N 477371 - Works well for high current situations. Filter package GM P/N 1224205 - Works well for low current situations. Fuel pump suppressor GM P/N 25027405 21 inch braided ground strap GM P/N 8910791 19 inch braided ground strap GM P/N 6286800 10.5 inch braided ground strap GM P/N 6287160 8.5 inch braided ground strap GM P/N 12091511

Generator Whine Concerns

1. Inspect the ground terminal and cable for high resistance.
2. Inspect the generator and brackets for loose or coated mounting bolts.
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. Refer to «Diagnostic Starting Point - Engine Electrical»(ref-187793-S30508022522005090100000) in Engine Electrical.
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 including those not related to the audio system, for proper operation and function.

Always perform the Entertainment System Diagnostic System Check before proceeding with these diagnostic procedures. Refer to Diagnostic System Check - Entertainment System .

Radio Displays LOC, LOCKED, or CODE

Radio Displays LOC, LOCKED, or CODE

Radio Displays CAL or CAL ERR

Radio Displays CAL or CAL ERR

Steering Wheel Controls Inoperative

Steering Wheel Controls Inoperative

Reduced Volume - One or More Speakers

Schematic Reference: Radio/Audio System Schematics

Always perform the Entertainment System Diagnostic System Check before proceeding with these diagnostic procedures. Refer to Diagnostic System Check - Entertainment System .

Speakers - Reduced Volume

Without RPO UQA

1. Speaker output circuit high resistance-Test the appropriate speaker output circuits for high resistance. Refer to «Circuit Testing»(ref-187796-S41173270102005090100000) and «Wiring Repairs»(ref-187796-S26318282122005090100000) in Wiring Systems.
2. Defective speaker-Replace the appropriate speaker. Refer to «Speaker Replacement Reference»(ref-187801-S28210395402005090100000) .

With RPO UQA (Bose)

1. Speaker output circuit high resistance-Test the appropriate speaker output circuits for high resistance. Refer to «Circuit Testing»(ref-187796-S41173270102005090100000) and «Wiring Repairs»(ref-187796-S26318282122005090100000) in Wiring Systems.
2. Front low level audio circuit open-Test the appropriate low level audio circuit for an open. Refer to «Circuit Testing»(ref-187796-S41173270102005090100000) and «Wiring Repairs»(ref-187796-S26318282122005090100000) in Wiring Systems.
3. Defective speaker-Replace the appropriate speaker. Refer to «Speaker Replacement Reference»(ref-187801-S28210395402005090100000) .

Speakers Inoperative - One or More

Schematic Reference: Radio/Audio System Schematics

One Speaker Inoperative

Without RPO UQA

1. Speaker output open-Test the appropriate speaker output circuits for an open. Refer to «Circuit Testing»(ref-187796-S41173270102005090100000) and «Wiring Repairs»(ref-187796-S26318282122005090100000) in Wiring Systems.
2. No audio output from the radio-Test for any AC voltage between the appropriate speaker output circuits at the speaker harness connector, disconnected with the radio volume adjusted to an audible level. If AC voltage is present, replace the speaker. Refer to «Speaker Replacement Reference»(ref-187801-S28210395402005090100000) . If no AC voltage is present, replace the radio. Refer to «Radio Replacement»(ref-187801-S36498379372005090100000) .

With RPO UQA (Bose)

1. Speaker output circuit from amplifier open or shorted-Test the appropriate speaker output circuits for an open or short. Refer to «Circuit Testing»(ref-187796-S41173270102005090100000) and «Wiring Repairs»(ref-187796-S26318282122005090100000) in Wiring Systems.
2. No audio output from the amplifier-Test for any AC voltage between the appropriate speaker output circuits at the speaker harness connector, disconnected with the radio volume adjusted to an audible level. If AC voltage is present, replace the speaker. Refer to «Speaker Replacement Reference»(ref-187801-S28210395402005090100000) . If no AC voltage is present, replace the amplifier. Refer to «Amplifier Replacement»(ref-187801-S02824858952005090100000) .

Radio Signal

The radio signal is sent from a broadcast station and is then received by an antenna. The strength of the signal received depends on the following

1. The power output (wattage) of the broadcasting station
2. The location of the vehicle (or receiver) relative to the broadcast tower.
3. Obstacles between the tower and the receiver
4. Atmospheric conditions
5. What band (AM or FM) the station is broadcasting
6. Type of antenna and the ground plane

AM Reception

The AM band has a lower frequency range than the FM band. These longer wavelengths

1. Bend around Obstacles
2. Follow the curvature of the earth
3. May reflect off the ionosphere (skip)

The AM frequencies have longer range due to the ground wave. The ground wave follows the curvature of the earth and is effected by its conductivity. Greater conductivity equates to less signal loss thus transmission over water is better than over land. The AM band has a range of 80-320 km (50-200 miles).

FM Reception

The shorter wavelengths of the higher frequency FM band

1. Reflect off obstacles
2. Are absorbed by the ground
3. Penetrate the ionosphere

Broadcasts in the FM band are limited to "line of sight" reception which is typically 40 km (25 miles). Even when out of a direct line of sight, the signal may be reflected into areas that would be in a shadow otherwise. Factors which affect the line of sight include

1. Height of the broadcast antenna
2. Height of the receiving antenna
3. Terrain and buildings in the broadcast path

Audio Amplifier

The audio amplifier is optional. The radio supplies low level audio signals to the audio amplifier in order to boost the signal sent to the speakers. The class 2 signal circuit allows the radio to recognize that an amplifier is present. Once the radio detects an audio amplifier, it will output low level audio signals. The audio amplifier is turned on when it receives a message via the class 2 serial data circuit indicating that the radio is on.

Theft Deterrent

The theft deterrent system is a feature on all base and uplevel radios. There is no need to program a security code into the radio as in past model years. The theft deterrent system now utilizes class 2 serial data to determine if the radio is in the appropriate vehicle. Each time the radio receives the "run" power mode message, it compares the vehicle identification number (VIN) information it has stored to the VIN information received from the body control module (BCM) on the class 2 serial data circuit. If a mis-match occurs, the radio display will indicate to the user the radio is locked. Once this takes place the radio will not respond to any button presses and become inoperative. The two scenarios able to cause this condition are

1. A radio is installed from another vehicle
2. The BCM is replaced and not properly setup with the correct VIN information for that vehicle

The only way to unlock the radio is by using a scan tool.

Integral Multi Disc CD Changer (IMDX)

The integral multi disc CD changer has the capability of storing and playing up to 6 compact discs. The integral multi disc CD changer has a shock-absorbing system. Only under extreme operating temperatures or severe shock or vibration should the compact disc player skip or mute. If the customer travels an abnormally rough road, a skip condition may be normal. Test drive the vehicle on a normal road with a known good CD. If the condition is still present, replace the radio.

The use of CD lens cleaner discs is not advised, due to the risk of contaminating the lens of the CD optics with lubricants internal to the CD mechanism.

Single Disc Loading

To operate the integral multi disc CD changer in the single play mode, press the LOAD button for less than 2 seconds. The LED to the right of the disc door will turn green to indicate the CD can be loaded. Insert the disc into the slot, label side up. The player will pull the disc in.

Multi Disc Loading

To operate the changer in the multi disc mode, press the LOAD button for more than 2 seconds and the LED to the right of the disc door will flash. Once the light stops flashing and turns green you can load a disc. Insert the disc into the slot, label side up. The player will pull the disc in. Once the disc is loaded, the light will begin flashing again. Once the light stops flashing and turns green you can load another disc.

Removing CDs

Use the eject button to remove a disc or discs. Perform the following to eject

1. To remove a single disc, press and release the eject button. The message REMOVE CD is displayed.
2. To remove multiple discs, press and hold the eject button for 2 seconds. An audible beep is heard and the LED to the right of the disc door begins to flash indicating a disc is being ejected. The message REMOVE CD is displayed.

Radio Data System (RDS)

All audio systems are equipped with technology known as the radio data system (RDS). RDS is a system that sends data along with the audio of the FM station you are currently tuned to. RDS is a standard that defines how a FM broadcast station may send digital data along with the audio program. Think of it as a one way wireless modem, allowing the broadcaster to send information about his program to your receiver.

RDS data is carried in what is known as a "sub-carrier". A sub-carrier is a frequency that the FM broadcaster is authorized to use to send data or other audio programs that are not audible in the main audio program. RDS information can be used to display program information and to control the radio.

To receive the RDS signal, all that is needed is an FM receiver with a RDS circuit. A special integrated circuit capable of dealing with the RDS signal is in the RDS circuit and passes it along to the receiver's microprocessor where it is decoded and acted upon.

RDS Basic Information

RDS basic information

1. RDS functions are provided in the FM broadcast band only.
2. RDS functions will only work with FM broadcast stations that are broadcasting RDS data.
3. Not all FM Broadcast stations broadcast RDS data or offer all of the RDS services.
4. RDS functions may not work properly when reception is weak, reception is of poor quality, or RDS is not implemented properly by the FM Broadcaster.

In some cases, a radio station broadcasting incorrect information may cause the RDS features of the radio to appear to work improperly.

Broadcast RDS information can be used in a variety of ways by the receiver and listener, but basically falls into two categories: Display and Control.

Displaying Program Information

RDS displays textual information such as

1. The name of the station.
2. The type of program.
3. General information such as artist and song title, call in phone numbers, etc.

RDS is always on. When tuned to a non-RDS station, your radio will display frequency information as you would normally expect. When tuned to a RDS station, your radio will change from displaying the frequency of the FM station to displaying the call letters of the station or display the nickname of the station. This feature is known as the Program Service Name.

Controlling the Radio

RDS can control the radio when data the receiver can use responds to timely information performing the following

1. Interrupt the playback of your cassette or CD for traffic or emergency bulletins.
2. Search for stations by type of program.
3. Automatically follow networked programming from transmitter to transmitter as you travel from one listening area to another.
4. Set your clock to the time that the RDS Broadcast station broadcasts.

Viewing and Selecting RDS Information for Display

Press the TUNE knob once for less then 2 seconds when the radio displays the program service name and the frequency of the station will be displayed. Press the knob again, and the program type (PTY) will be displayed. Pressed again, and the program name will be displayed, if the broadcaster is broadcasting one. The program name is an 8-character name that the broadcaster may use to further identify the type of programming currently being broadcast.

Using the RDS Traffic Feature

Some RDS broadcasters may carry traffic information programming to inform you of current traffic conditions in your listening area and is indicated by the icon in the radio display. RDS enables the broadcaster to get this information to you even when you are listening to a tape or compact disc. This feature can be enabled or disabled by the listener. Press the TRAF button to find a station that claims to carry traffic information. You may do this even when playing a cassette tape or compact disc. This action will operate in the background without interrupting the current playback. If the radio is not currently tuned to an RDS traffic station, the radio will immediately SEEK an RDS traffic station. If the radio finds an RDS traffic station, the TRAF icon will appear in the radio display as will brackets around the (TRAF) icon. If the radio cannot find an RDS traffic station after searching through the entire FM band, the radio will display NO TRAFFIC.

Alternate Frequency (AF) Switching

RDS permits broadcasters to send information to the radio that allows the radio to automatically switch frequency to the best quality station in that broadcaster's network.

Since the radio is displaying the broadcaster call letters or nickname, the listener will not see the frequency during an AF switch unless you have changed the default display to be frequency instead of Program Service name.

To enable or disable AF switching perform the following

1. Press and hold the BAND button for 2 seconds or more.
2. The radio will display AF ON or AF OFF depending on the current condition of AF and a confirmation beep will be heard.

When AF is enabled and you recall a RDS station stored on preset, the radio determines if the station stored is of acceptable quality. If not, the radio checks all available AF's for your station. If the radio fails to locate your program, AF SEARCH will be displayed as the radio scans across the band looking for your program or an affiliated network. If the radio cannot find the original station or an acceptable alternate frequency NOT FOUND will be displayed and the radio returns to the original frequency for the preset.

RDS Clock Time

Broadcasters can choose to send clock time information in the RDS data. This information can be used to update the clock time on the radio. RDS clock time is broadcasted once a minute. To set the clock using RDS clock data perform the following

1. Press and hold the HR and MIN buttons together for 2 or more seconds to update the time.
2. The display will show UPDATED after receiving the broadcasted time data.
3. If the broadcaster is not broadcasting the time data, the radio will display NO UPDATE and the time remains unchanged.