GM Service Manual Online
For 1990-2009 cars only

Caution: Pacemakers and other medical equipment may be affected by a mobile phone transmission. DO NOT use the telephone when any person is within 0.6 meter (2 feet) of the antenna or death may result.

Caution: Turn off the cellular telephone when refueling. Do not carry containers of fuel in the rear compartment or inside the vehicle or an explosion of fire may result with personal injury.

Caution: Using a cellular telephone while driving a vehicle is not advised. The distraction can cause a crash with possible personal injury. If calls must be initiated from a moving vehicle, use caution at all times.

Important: Refer to the User's Guide that accompanies the cellular phone for information on special functions not covered in this section. Some of the information may change as a result of telephone function and programming changes from the manufacturer.

Vehicle occupants may place and receive telephone calls with a cellular mobile telephone. The vehicle must be in a geographic location which is serviced by a cellular telephone site. The mobile telephone includes voice recognition which allows the following procedures to be done by voice usage only:

    • Dialing
    • Memory Retrieval
    • Credit Card Calling

These features operate in conjunction with the following systems:

    • The Audio System
    • The Steering Wheel Controls
    • The Driver Information Center

The voice recognition will recognize the user's voice without being programmed. The system has 400 different voice types that are automatically programmed into the voice recognition feature. The system uses a hands-free microphone for voice recognition.

Cellular Telephone Handset

The cellular telephone handset is located in the forward compartment of the console. Place the handset in the ON position in order to place or receive calls.

Hands Free Operation

Hands free operation allows the occupants in the vehicle to converse without using the handset. Hands free operation is automatic during the conversation. The conversation is carried on by the use of the hands-free microphone and the audio system speakers.

Cellular Microphone

The cellular microphone is located in the inside rearview mirror. The microphone operates while in hands-free mode. While in the hands-free mode, the user may mute the microphone during a call. Use the mute function in order to speak privately with a passenger.

Cellular Telephone Module

The cellular telephone module is located in the rear compartment, behind the rear shelf trim, mounted to the rear shelf carrier. The module provides the following features:

    • Hands-free cellular telephone integration
    • Steering wheel controls operation
    • Voice recognition
    • Memo record
    • Driver display

Cellular Telephone Antenna

The 3-decibel noiseless antenna is mounted on the right side of the rear window glass.

Celular Telephone Circuit Description

Power is supplied from the AUDIO fuse in the rear fuse block via CKT 2240 to the cellular telephone module. The module is grounded via CKT 1051 to ground G401.

The module controls the cellular telephone handset power via CKT 1941 and CKT 2526. The module controls the handset display and transfers handset/keypad data on CKT 679, CKT 1156 and CKT 1798.

The handset communicates shielded signals to the cellular telephone module as follows:

    • Mouthpiece audio CKT 1153
    • Earpiece audio CKT 1235
    • Audio low reference CKT 1155

When the handset is placed in the docking station, the system operates in the hands-free mode. This mode enables the hands-free microphone to pick up the the driver's voice. During hands-free mode, the radio amplifier mutes the radio or cd changer audio signal and sounds the the incoming cellular telephone voice audio signal through the speakers. Removing the handset from the docking station disables the hands-free feature, which allows the radio amplifier to play the radio or cd changer audio signal. The handset must be held to the driver's head for voice conversation.

The cellular telephone microphone is wired to the cellular telephone module via CKT 655 and CKT 814. During hands-free operation, the module provides mono audio output to the vehicle audio system on CKT 658 and CKT 659 .

The module communicates on the Class 2 serial data line CKT 1807, which the module uses for transmission of messages, status and diagnostic information.

Basic Phone Operations

    • Press the PWR key for at least one second until the phone handset display is illuminated, to turn the phone ON.
    • Press the PWR key for at least one second until the phone handset display is dark, to turn the phone OFF.
    • Enter the number on the keypad and press the SND key to place a call.
    • Press the END key to end a call.
    • The phone must be ON to receive a call. Press SND when the phone rings or press any other handset key other than the volume key or PWR key when the phone rings.
    • There are many features in the function menu along with personalization of phone directories that can be modified by the owner.
    • Numbers may be prestored under a specified voice name tag for later ease of use with future phone operation.

Message Display

Message Display provides a visual indication of telephone numbers and messages associated with mobile telephone service.

No Service Indicator (NOSVC): The No Service Indicator illuminates when the unit is out of the range of the cellular system or when the selected system registration restricts operation in the service area. Calls cannot be placed or received. The NOSVC flashes slowly in areas of marginal coverage.

Roam Indicator: The Roam Indicator illuminates solid when the unit is within the range of a cellular system other than its home registered range operating on the same frequency. The flashing ON/OFF indicates the operation with alternate service provider from the home system.

In Use Indicator: The In Use Indicator illuminates when a call is initiated or answered. There are no dial tones on cellular phones.

Signal Strength Indicator: The Signal Strength Indicator is represented by 3 full blocks that represents the strength of the cellular signal. The indicator is shown after the Phone menu logo on the DIC display and in the upper left corner of the handset. Three full blocks represent a very strong signal strength. As signal strength decreases, the blocks will go down accordingly.

Digital: The Digital indicates service from a digital cellular service provider.

Voice Recognition (VR): The Voice Recognition on the DIC indicates that the phone is in voice recognition mode.

Keypad Buttons

Clear Key (CLR): Press CLR to clear the entered number in the event of an error. This does not affect the stored numbers in memory.

Send (SND): Press SND to initiate a call to the entered telephone number or to answer an incoming call.

End: Press END to terminate a call. This will also end the memory stroll mode.

Power Key (PWR): Press PWR until you hear a tone to turn the phone ON. Press PWR until a tone is heard again to turn the phone OFF.

Store Key (STO): Press STO and the location number (01-99) to store telephone numbers into any of the 100 memory locations. It can also be used to confirm personalized locations.

Recall Key (RCL): Press RCL and the location number (1 - 99) to recall and display telephone numbers stored in the memory.

Numeric Pad (0 - 9,*,#): Press 0 - 9,*,# to enter the telephone numbers. Enter numbers prior to initiating a call.

Function Key (FCN): Press FCN to activate the following features of the mobile telephone:

    • Volume
    • In Service Use
    • Current Time Usage
    • Telephone Personalization
Voice Recognition: Press VR to allow entry into the voice recognition mode.

M1: Press M1 for one touch dialing. A number can be stored in this location and dialed directly.

Volume Control: The Volume Control adjusts audio from the following phone components:

    • The keypad
    • The speaker
    • The earpiece
    • Volume control is also used to scroll through the memory and feature menu.

Steering Wheel Controls

Phone Switch: Press the Phone switch up in order to transition the phone from the ON state to the ACTIVE state. This action also activates the voice recognition (VR) mode.

Recall Switch: Press the Recall switch down in order to scroll through the last 5 numbers dialed.

Send Switch: Press the Send switch up in order to dial a telephone number.

End Switch: Press the End switch down in order to end a call.

Select Switch: Press the Select switch up or down in order to scroll through the stored numbers in the memory.

Volume Switch: Press thte Volume switch up or down in order to adjust the volume up or down.

Feature Descriptions

For detailed cellular telephone operation instructions, refer to the Owner's Cellular Phone System Supplement and the Cellular Telephone User Manual.

Placing a Call Through the Handset Keypad

In order to dial a number, use the following procedure:

  1. Press SND to initiate the call.
  2. Press END after the call is completed.

In order dial a number by recalling a specific memory location, use the following procedure:

  1. Press RCL.
  2. Enter two digits of the desired memory (01,05, etc.).
  3. Press SND to initiate the call.
  4. Press END after the call is completed.

In order to dial a number from the scrolling phone memory, use the following procedure:

  1. Press RCL.
  2. Scroll the phone memories with the volume control keys on the left side of the handset.
  3. Stop the scrolling when the desired number is reached.
  4. Press SND to initiate the call.
  5. Press END after the call is completed.

Placing Calls Using the Steering Wheel Controls (SWC)

  1. Tap up on the Phone switch to access the phone mode.
  2. Tap up or down and hold the Select switch to scroll the phone memories for the desired phone number. Phone numbers can be seen on the DIC display.
  3. Tap up the SND switch to initiate the call.
  4. Tap down on the END switch after the call is completed.

Placing Calls Using Voice Recognition

  1. Tap up and hold the phone switch for one second to access the phone's VR mode. A second option is to press the VR key on the handset.
  2. Speak the word Dial after the Ready Voice prompt.
  3. Speak the phone number you wish to dial after the Number Please voice prompt. After each spoken digit, the number appears on the DIC.
  4. Speak the word Dial. The dialing voice prompt follows.
  5. Speak the word Send in order to initiate a call.
  6. Tap down on the END switch or press the END key on the handset, after the call is completed.

Important: 

   • Speaking the word Clear may be used to undo the last spoken digit.
   • Speaking the word Help after the voice prompt provides a list of commands via voice recognition.
   • Speaking the word Cancel takes you to the top of the VR command list.

Cellular Telephone -- Driver Information Center Messages

The cellular telephone module and instrument cluster communicate via class 2 serial data. This communication allows the cellular telephone module to provide status and message information to the cluster for display on the driver information center (DIC). A driver may display the cellular telephone status messages by pressing the INFO DIC button up or down, then navigating through the various display parameters (such as fuel used, average vehicle speed, etc.) until the cellular telephone status display appears.

The following is a list of cellular telephone status information and messages. When the message listed is divided by a dash (--), the second portion of the message is right justified on the DIC.

Received Signal Strength Indicator

The display indicates the signal strength from the cell site that the cellular telephone is currently detecting. The received signal strength indicator uses the 3 characters following PHONE on the DIC. Each character is capable of displaying 5 bars to represent signal strength. The DIC can display the signal strength level within the range 0 to 15. The received signal strength indicator is only displayed for certain cellular telephone status information and messages.

Phone Alphanumeric Display

The display indicates a recall of a text string or phone number from a memory location. The display will include the received signal strength indicator display. The phone alphanumeric display is displayed as PHONE -- XX XXXXXXXXXX. The 2 digit XX represents the number for the memory location in the cellular telephone. The 10 digit XXXXXXXXX represents the text string or phone number stored in the memory location. A text string may contain letters and numbers.

PHONE -- CALL

The message indicates that an incoming call has been received by the cellular telephone. The message will include the received signal strength indicator display. The message can be displayed as a driver status message.

Phone Call Timer

The display indicates the length of time for a call is in progress or the running call timer is displayed. The phone call timer is displayed PHONE -- TIMER XX:XX. The first XX represents minutes elapsed and the second XX presents seconds elapsed. The display will include the received signal strength indicator display. The display can be displayed as a driver status message.

The timer can be set to display the time for an individual call or set to display the running call time. The programming function is performed through the cellular telephone handset.

Phone Digit Dialing

During phone digit dialing, the cellular telephone key pad is be used to enter a phone number to be called. The display will include PHONE and the received signal strength indicator display. Up to 14 digits can be used to display the digits being dialed. The digits will start at the far right of the display and scroll from right to left as more digits are dialed. If more than 14 digits are dialed, only the last 14 digits will be displayed.

When the CLEAR button is pressed on the telephone handset, the cellular telephone deletes the last digit dialed. The digit is also removed from the DIC display and the remaining digits are scrolled one digit to the right.

Phone Incoming Caller ID

The display indicates an incoming telephone call has been received by the cellular telephone and the caller's ID can be identified. The display will include the received signal strength indicator display. The phone incoming caller ID is displayed as PHONE -- XXXXXXXXXX. The 10 digit XXXXXXXXX represents the text string or phone number of the incoming caller. A text string may contain letters and numbers.

PHONE -- LOCKED

The message indicates that the cellular telephone is currently locked and that an unlock code is required to use the cellular telephone. The message will include the received signal strength indicator display. The message can be displayed as a driver status message or in the vehicle information display.

PHONE -- NO HANDSET

The message indicates that the cellular telephone handset is physically disconnected. The message can be displayed as a driver status message or in the vehicle information display.

PHONE -- NO SERVICE

The message indicates that the cellular telephone service is not currently available. The message can be displayed as a driver status message or in the vehicle information display.

PHONE -- NOT PRESENT

The message indicates that the vehicle is configured to have a cellular telephone, but the cellular telephone is not communicating with the IPC. Under the above conditions, the message will be displayed when either the cellular telephone status is displayed in the vehicle information display or the driver activates the cellular telephone by pressing the PHONE or RECALL buttons on the steering wheel controls.

PHONE -- OFF

The message indicates that the cellular telephone power button is in the state of OFF. The message can be displayed as a driver status message or in the vehicle information display.

PHONE -- ON

The message indicates that the cellular telephone power button is in the state of ON, but no other active conditions currently exist. The message will include the received signal strength indicator display. The message can be displayed as a driver status message or in the vehicle information display.

PHONE -- PAUSE

The message indicates that the cellular telephone is currently in pause status. The message will include the received signal strength indicator display. The message can be displayed as a driver status message.

PHONE -- ROAM A

The message indicates that the cellular telephone is currently in roam A status. The message will include the received signal strength indicator display. The message can be displayed as a driver status message or in the vehicle information display.

PHONE -- ROAM B

The message indicates that the cellular telephone is currently in roam B status. The message will include the received signal strength indicator display. The message can be displayed as a driver status message or in the vehicle information display.

Phone Volume

The display indicates the level of the cellular telephone volume. The phone volume displays the PHONE with the received signal strength indicator display, which is followed by 3 blank characters on the DIC. After the 3 blank characters, the phone volume displays VOL and a blank character on the DIC. Then, the following 7 characters are use to display the level of the phone volume. Each character is capable of displaying 5 bars to represent volume. The DIC can display the phone volume level within the range 0 to 35. The display can be displayed as a driver status message.