Component Checking/Testing/Identification
FUSE, CHECKINGEarly 1991 my.
On early production 1991 m.y. vehicles, the fuse for the telephone is located underneath the transceiver mounting bracket, below the trunk carpeting.
To replace or check the fuse:
^ remove telephone transceiver from mount
^ remove securing screws (arrows) and remove transceiver mount
^ remove right side trunk carpet securing screws and fold back carpet
^ fuse holder A mounted below transceiver bracket
^ check fuse
^ 10 amp
Late 1991 my.
On late 1991 m.y. vehicles, the fuse is located behind the battery, under the rear seat.
^ remove rear seat bottom to access fuse
8-PIN MODULAR CONNECTOR ON HANDSET, TERMINAL IDENTIFICATION
1 - Handset logic ground (-), blue (to terminal 23 on 25-pin connector)
2 - Regulated 9.6 V (+), red (to terminal 8 on 25-pin connector)
3 - T-data communication line, purple (to terminal 11 on 25-pin connector)
4 - C-data communication line, orange (to terminal 12 on 25- pin connector)
5 - R-data communication line, yellow (to terminal 18 on 25- pin connector)
6 - Handset audio ground (-), brown (to terminal 24 on 25-pin connector)
7 - On/Off function, transmit audio, green, (to terminal 1 on 25-pin connector)
8 - Receive audio, white, (to terminal 6 on 25-pin connector)
25-PIN CONNECTOR TO TRANSCEIVER, TERMINAL IDENTIFICATION
CAUTION
DO NOT damage, enlarge or bend connector pins or cavities by forcing probes into them when performing electrical checks.
Illustration identifies the 25-pin connector as it appears on the wiring harness.
1 - On/Off function, transmit audio (to terminal 7, green, on handset)
2 - Mobile/transportable select line
3 - Ground (GND) (black wire)
^ one of two Grounds required for proper operation. Other Ground is at pin 17
4 - Plus connection (B+), terminal 30 (red wire)
^ one of two B+ connections required for proper operation. Other B+ connection is at pin 16
5 - Plus connection (B+) terminal 15, ignition sense lead (green/black wire)
6 - Receiver audio to handset (to terminal 8, white,on handset)
7 - Configuration (not applicable)
8 - Regulated +9.6V (to terminal 2, red, on handset)
9 - Power antenna (B+) feed (not applicable)
10 - Radio mute signal (yellow/black wire)
11 - T-data communication line (to terminal 3 purple on handset)
12 - C-data communication line (to terminal 4, orange, on handset)
13 - Open
14 - Transmit audio shield, to hands-free microphone
15 - Transmit audio, to hands-free microphone
16 - Plus connection (B+), terminal 30 (red wire)
^ one of two B+ connections required for proper operation. Other B+ connection is at pin 4.
17 - Ground (GND) (black wire)
^ one of two Grounds required for proper operation. Other Ground is at pin 3.
18 - R-Data communication line (to terminal 5, yellow, on handset)
19 - Receiver audio, to hands-free speaker
20 - Ground (GND) for receiver audio (shield) to hands-free speaker
21 - Manual test lead (Test Mode)
22 - Open
23 - Handset logic Ground (-) (to terminal 1, blue, on handset)
24 - Handset audio ground (GND) (to terminal 6, brown, on handset)
25 - Accessory Ground (GND), to hands-free speaker
ANTENNA PERFORMANCE, CHECKING
^ insert test connector US 30844 (arrow) in line between power cord (25-pin connector) 1 and transceiver 2
^ switch ignition ON
^ switch phone ON by pressing "Pwr" button on handset
^ observe flashing display on handset
^ two sets of numbers will alternately be displayed;
for example:
First set - "366 023"
Second set- "3000111"
Note
The first set of numbers will be constantly changing. The first three numbers on the left indicate the control channel number, and the three numbers on the right represent the Receiver Signal Strength Indicator (RSSI). The RSSI reading is used to indicate the strength on incoming signals.
The second set of numbers represents control functions of the telephone and is not used in our diagnosis.
^ with vehicle's antenna connected, read strength of RSSI readings and note an average
^ turn phone OFF
^ substitute vehicle's antenna with magnetic mount test antenna US 30845
^ turn phone ON
^ observe flashing display on handset
^ read strength of RSSI readings and compare to average readings received from vehicle's antenna
^ RSSI reading of vehicle's antenna must not vary by more than -10 units
^ replace vehicle antenna if its RSSI readings are more than 10 units below that of magnetic mount test antenna US 30845
HANDS-TREE SYSTEM, CHECKING
^ insert test connector US 30844 (arrow) in line between power cord (25-pin connector) 1 and transceiver 2
^ switch ignition ON
^ switch phone ON by pressing "Pwr" button on handset
^ handset readout displays two alternating sets of numbers
Note
This procedure can also be performed with the ignition switch OFF. However, when the phone is switched ON, the display may show "Loc'd". To proceed, press the "# " key to enter the Test Mode directly.
^ press "# " key to enter Test Mode
^ handset readout displays "US" with an apostrophe (') in the upper right hand corner
^ enter diagnostic command 350 # by pressing keys "3", "5", "0" and "# "
^ enter diagnostic command 48 # by pressing keys "4", "8", and "# "
^ tap microphone lightly while listening to hands-free speaker
^ must hear audio from speaker
^ if NO, refer to hands-free operation troubleshooting
^ to exit test mode, switch phone OFF
^ remove test connector
Note
All hands-free system components (microphone, speaker, wiring, etc.) are verified by successful completion of this check.
LOCKOUT COUNTER, RESETTING (DIAGNOSTIC COMMAND 32 #)
The telephone is designed to allow up to three changes of the phone number. After three changes, (and three presses of the "Snd" button) the phone will lock out any further attempts at programming.
To unlock/reset phone:
^ insert test connector US 30844 (arrow) in line between power cord (25-pin connector) 1 and transceiver 2
^ switch ignition ON
^ switch phone ON by pressing "Pwr" button on handset
^ handset readout displays two alternating sets of numbers
Note
This procedure can also be performed with the ignition switch OFF. However, when the phone is switched ON, the display may show "Loc'd". To proceed, press the "# " key to enter the Test Mode directly.
^ press "# " key to enter Test Mode
^ handset readout displays "US" with an apostrophe (') in the upper right hand corner
^ enter diagnostic test command 32 # by pressing keys "3", "2" and "# "
^ counter reset is now activated
^ when-counter reset is complete, handset readout displays an apostrophe (') in the upper right hand corner
^ switch power OFF and remove diagnostic test connector
Note
The 32 # command resets all user programmable features to standard and clears all timers and user stored memory (e.g., customer's stored personal phone numbers).
^ re-program user information as necessary
ELECTRONIC SERIAL NUMBER (ESN), CHECKING (DIAGNOSTIC TEST COMMAND 38 # )
^ insert test connector US 30844 (arrow) in line between power cord (25-pin connector) "1" and transceiver "2"
^ switch ignition ON
^ switch phone ON by pressing "Pwr" button on handset
^ handset readout displays two alternating sets of numbers
Note
This procedure can also be performed with the ignition switch OFF. However, when the phone is switched ON, the display may shown "Loc'd". To proceed, press the "# " key to enter the Test Mode directly.
^ press "# " key to enter Test Mode
^ handset readout displays "US" with an apostrophe (') in the upper right hand corner
^ enter diagnostic command 38 # by pressing keys "3". "8", and "# "
^ electronic serial number identification begins, first display is shown ("00 82" or "00 C3")
Note
The electronic serial number (ESN) readout is divided into four separate displays each showing two characters of the ESN. The number on the left indicates the step of the identification process (00 through 03), and the two characters on the right indicate a portion of the ESN.
For example:
First display: "00 82" or "00 C3" Second display: "01 0A" Third display: "02 16" Fourth display: "03 F7" ESN = 820A16 F7 or C30A16 F7
^ press "*" key to advance from display to display
^ repeated pressing of "*" button will cycle displays (00 to 03) continuously
^ write down each part of ESN (two characters) at each step
^ press "# " key to exit test mode
^ handset readout displays an apostrophe (') in the upper right hand corner
^ switch phone OFF and remove test connector
^ compare displayed ESN to ESN printed on bar-code label on rear of transceiver
If displayed ESN does not match printed ESN by one or two digits
^ contact Cellular Phone Company and make arrangements to activate correct (displayed) ESN
If displayed ESN is scrambled and does not resemble printed ESN
^ replace transceiver
CAUTION
Each transceiver has its own electronic serial number (ESN). ALWAYS register a new transceiver with the Cellular Telephone Company before placing a call.
SECURITY CODE, IDENTIFYING (DIAGNOSTIC TEST COMMAND 55 # )
Use the following procedure when phone programming is not possible due to an unknown or forgotten six-digit security code. This procedure is also used to determine a forgotten lock code or phone number.
^ insert test connector US 30844 (arrow) in line between power cord (25-pin connector) 1 and transceiver 2
^ switch ignition ON
^ switch phone ON by pressing "Pwr" button on handset
^ handset readout displays two alternating sets of numbers
Note
This procedure can also be performed with the ignition switch OFF. However, when the phone is switched ON, the display may show "Loc'd". To proceed, press the "# " key to enter the Test Mode directly. -
^ press "# " key to enter Test Mode
^ handset readout displays "US" with an apostrophe (') in the upper right hand corner
^ enter diagnostic command 55 # by pressing keys "5", "5", and "# "
^ test mode programming begins on step one
^ five-digit system identification number is displayed (for example, "00000")
Note
Sixteen different steps, each containing telephone programming information, can be displayed during this test mode.
"*" key - advances to next programming step
"# " key - exits program mode
^ press "*" key six times to display six digit security code (step 7)
Note
Press "*" key two times to display phone number (step 3) or seven times to display three-digit unlock code (step 8).
^ write down needed information
^ press "# " key to exit test mode
^ handset readout displays an apostrophe (') in the upper right hand corner
^ switch phone OFF and remove test connector
Test Mode Programming Chart (55 # )
Telephone Does Not Switch On
"NoSvc" Light Stays On
Fast Busy Signal or Recording Received When Placing Calls.
Telephone Does Not Operate In Hands-Free Mode
Static On Calls
Telephone does not respond to voice commands (voice recognition does not work) (if applicable)
Test requirements
^ hands-free system OK
^ verify customer is operating and training voice recognition system properly
^ always refer to Operating Instructions Manual for proper programming and training instructions
^ ensure handset is hung up (system will not work if handset is off cradle)
Test Procedures
Voice Recognition Does Not Operate Properly (if applicable)