Hummer H2. Manual — part 288

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 VIN information it has stored to the VIN information received from a module on the class 2
serial data circuit responsible for transmitting that information. If a mis-match occurs, the radio display will
indicate to the user the radio is locked. Once this takes place, a DTC will set, the radio will not respond to any
button presses and become inoperative. The two scenarios able to cause this condition are:

z

A radio is installed from another vehicle

z

A module which communicates on the class 2 serial data circuit which supplies VIN information to the
radio 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. Always refer to the table in this section to diagnose the
"Theftlock" DTC for further information.

Integral Multi Disc CD Changer (IMDX)

The Integral Multi Disc CD Changer has the capability of storing and playing up to six (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.

To operate the Integral Multi Disc CD Changer in the single play mode, depress the LOAD button for less than
2 seconds, an audible beep can then be heard. When the disc door opens the LED to the right of the disc door
will first turn red then green to indicate the CD can be loaded. The radio will also display the message INSERT
CD 1 and the changer will pull the disc into the play position. To operate the changer in the multi disc mode,
depress the MODE button for more than two seconds and the LED to the right of the disc door will first turn red
then green to indicate CDs can be loaded. The radio will also display the message MULTI LOAD to indicate
the multi load mode has been initiated and the changer will begin accepting a disc for however many empty
slots there may be. If eight seconds elapse before the next disc is loaded, the multi load mode is cancelled and
can be re-initiated if desired by depressing the load button again for more than two seconds. If the changer is
full, (6 discs are loaded) the single play and multi load modes cannot be executed. When this occurs, three
audible beeps are heard and the message CHANGER FULL is displayed.

Remote Playback Device

The remote playback device is either installed at the factory or in some instances it is dealer installed. There are
three types of remote playback devices, a multi disc remote CD changer, a single disc CD player and a cassette
player. All three devices have a wiring harness which plugs into the back of the radio. The radio controls and
communicates with the remote playback device through a Entertainment and Comfort (E&C) or class 2
communication circuit.

2004 Hummer H2

2004 ACCESSORIES & EQUIPMENT Entertainment - Hummer H2

Remote CD Changer (CDX)

The remote CD changer allows for multiple compact disks to be played continuously without having to
manually change compact discs. Normal size discs may be played using the slots supplied in the magazine. The
magazine must first be loaded with discs before it can played. To load CD's, insert the CD's from bottom to top,
placing the discs in the magazine label side up. If a disc is loaded label side down, the disc will not play and an
error will occur. Care should be used to align and insert the disc into one disc tray only. Repeat this procedure
for loading all of the discs in the magazine. Once the discs are loaded into the magazine, push the magazine into
the changer in the direction of the arrow marked on the magazine. When the CD magazine is loaded, the
changer will begin checking for discs in the magazine. This will continue for up to 11/2 minutes, depending on
the number of discs loaded. To eject the magazine from the player, push the CD changer door. The door will
open. Then press the eject button. NOTICE: If the CD magazine fails to eject after the EJECT button has been
pressed, do not attempt to pry the magazine from the CD changer. Whenever a CD magazine with discs is
loaded in the changer, the CD changer symbol will appear on the radio display. If the CD changer is checking
the magazine for CD's, the CD symbol will flash on the display until the changer is ready to play.

Radio Data System (RDS)

All uplevel 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:

z

RDS functions are provided in the FM broadcast band only.

z

RDS functions will only work with FM broadcast stations that are broadcasting RDS data.

z

Not all FM Broadcast stations broadcast RDS data or offer all of the RDS services.

z

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.

2004 Hummer H2

2004 ACCESSORIES & EQUIPMENT Entertainment - Hummer H2

Displaying Program Information

RDS displays textual information such as:

z

The name of the station.

z

The type of program.

z

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:

z

Interrupt the playback of your cassette or CD for traffic or emergency bulletins.

z

Search for stations by type of program.

z

Automatically follow network programming from transmitter to transmitter as you travel from one
listening area to another.

z

Set your clock to the time that the RDS Broadcast station broadcasts.

Viewing and Selecting RDS Information for Display

Press the TUNE SELECT PUSH RCL 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 (P-
Type) will be displayed. Pressed again, and the program type name will be displayed (if the broadcaster is
broadcasting one). The program type name is an eight-character name that the broadcaster may use to further
identify the type of programming currently being broadcast. Should you decide that Frequency, P-Type or
program type name is more desirable to display when tuned to an RDS station than the Program Service Name,
press the TUNE SELECT PUSH RCL knob until the desired information is displayed, then press and hold for
more than 2 seconds. A beep should be heard and the radio will now display the selected information whenever
tuned to an RDS broadcaster. The radio will display frequency for all non-RDS broadcast stations.

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

2004 Hummer H2

2004 ACCESSORIES & EQUIPMENT Entertainment - Hummer H2

station after searching through the entire FM band, the radio will display NO TRAFFIC.

Alternate Frequency (AF) Switching

RDS permits broadcaster's 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:

z

Press and hold the AM/FM button for two seconds or more.

z

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 broadcast once a minute. To set the clock using RDS
clock data perform the following:

z

Press and hold the HR and MIN buttons together for two or more seconds to update the time.

z

The display will show UPDATED after receiving the broadcast time data.

z

If the broadcaster is not broadcasting the time data, the radio will display NO UPDATE and the time
remains unchanged.

Radio Error Messages

The radio displays the following error messages:

CDX ERR

Displays if communication is lost with the remote CD changer (if equipped).

CHECK CD

Displays when the player encounters a focus or tracking error.

2004 Hummer H2

2004 ACCESSORIES & EQUIPMENT Entertainment - Hummer H2