Inspection Procedure 1

INSPECTION PROCEDURE 1: When the SPEECH button is pressed, the voice information is not output.

CAUTION:
Before replacing the module, ensure that the power supply circuit and the ground circuit are normal.






















CIRCUIT OPERATION

With the operation of the SPEECH button of the microphone switch, the hands-free module starts output to the radio and CD player or radio, CD player and CD changer for voice information. At this time, the voice information is output from the front door speaker (RH) and tweeter (RH) for the radio and CD player, and from the front speaker for the radio, CD player and CD changer.

TECHNICAL DESCRIPTION (COMMENT)

If the voice information is not output when the SPEECH button is pressed, the microphone switch, hands-free module, radio and CD player or radio, CD player and CD changer, or power supply circuit to the hands-free module may be faulty.

TROUBLESHOOTING HINTS

- The wiring harness or connectors may have loose, corroded, or damaged terminals, or terminals pushed back in the connector.
- Malfunctions of microphone switch
- Malfunction of hands free module
- Malfunction of radio and CD player or radio, CD player and CD changer

DIAGNOSIS

Required Special Tools:

- MB991223: Harness Set
- MB992006: Extra Fine Probe

STEP 1. Check the audio system.

Check that the audio system is activated normally, the voice is output from each speaker, and each of the audio information is shown on the display.

Q. Is the check result normal?

YES Go to Step 2.
NO Refer to G54A - radio with CD player Diagnosis Symptom Chart.
STEP 2. Check the microphone switch.

Refer to Component Tests and General Diagnostics.

Q. Is the check result normal?

YES Go to Step 3.
NO Replace the microphone switch.
STEP 3. Check hands-free module connector C-35 and microphone switch connector C-34 for loose, corroded or damaged terminals, or terminals pushed back in the connector.





Q. Are hands-free module connector C-35 and microphone switch connector C-34 in good condition?

YES Go to Step 4.

NO Repair or replace the damaged component(s). Harness Connector Inspection.

STEP 4. Check the wiring harness between hands free module connector C-35 (terminal 7) and microphone switch connector C-34 (terminal 3).





- Check the wiring harness for open circuit and short circuit.

Q. Is the wiring harness between hands free module connector C-35 (terminal 7) and microphone switch connector C-34 (terminal 3) in good condition?

YES Go to Step 5.

NO The wiring harness may be damaged or the connector(s) may have loose, corroded or damaged terminals, or terminals pushed back in the connector. Repair the wiring harness as necessary.

STEP 5. Check the ground circuit to the microphone switch. Measure the resistance at microphone switch connector C-34.





(1)Disconnect hands free microphone switch connector C-34, and measure at the wiring harness side.





(2)Measure resistance between terminal 2 and ground.
OK: The resistance should be 2 ohm or less.

Q. Is the measured resistance 2 ohms or less?

YES Go to Step 7.

NO Go to Step 6.

STEP 6. Check the wiring harness between microphone switch connector C-34 (terminal 2) and ground.





- Check the ground wire for open circuit.





NOTE:
Also check joint connector C-01 for loose, corroded, or damaged terminals, or terminals pushed back in the connector. If joint connector C-01 is damaged, repair or replace the connector as described in Harness Connector Inspection Harness Connector Inspection.

Q. Is the wiring harness between microphone switch connector C-34 (terminal 2) and ground in good condition?

YES The trouble can be an intermittent malfunction How to Cope With Intermittent Malfunctions).

NO The wiring harness may be damaged or the connector(s) may have loose, corroded or damaged terminals, or terminals pushed back in the connector. Repair the wiring harness as necessary.

STEP 7. Check radio and CD player C-118 or radio, CD player and CD changer C-119 for loose, corroded or damaged terminals, or terminals pushed back in the connector.





Q. Are radio and CD player C-118 or radio, CD player and CD changer C-119 in good condition?

YES Go to Step 8.

NO Repair or replace the damaged component(s). Harness Connector Inspection.

STEP 8. Check the wiring harness between radio and CD player C-118 (terminal 23, 28) or radio, CD player and CD changer C-119 (terminal 41, 29) and hands free module connector C-35 (terminal 9, 21).





- Check the wiring harness for open circuit and short circuit.

Q. Is the wiring harness between radio and CD player C-118 (terminal 23, 28) or radio, CD player and CD changer C-119 (terminal 41, 29) and hands free module connector C-35 (terminal 9, 21) in good condition?

YES Go to Step 9.

NO The wiring harness may be damaged or the connector(s) may have loose, corroded or damaged terminals, or terminals pushed back in the connector. Repair the wiring harness as necessary.

STEP 9. Check the power supply circuit to the hands free module. Measure the voltage at hands free module connector C-35.





(1)Disconnect hands free module connector C-35, and measure the voltage available at the hands free module side of the connector.





(2)Measure the voltage between terminal 13 and ground.
OK: The voltage should measure approximately 12 volts (battery positive voltage).

Q. Is the measured voltage approximately 12 volts (battery positive voltage)?

YES Go to Step 11.

NO Go to Step 10.

STEP 10. Check the wiring harness between hands free module connector C-35 (terminal 13) and battery.





- Check the wiring harness for open circuit and short circuit.





NOTE:
Also check intermediate connector C-24 for loose, corroded, or damaged terminals, or terminals pushed back in the connector. If intermediate connector C-24 is damaged, repair or replace the connector as described in Harness Connector Inspection Harness Connector Inspection.

Q. Is the wiring harness between hands free module connector C-35 (terminal 13) and battery in good condition?

YES The trouble can be an intermittent malfunction How to Cope With Intermittent Malfunctions).

NO The wiring harness may be damaged or the connector(s) may have loose, corroded or damaged terminals, or terminals pushed back in the connector. Repair the wiring harness as necessary.

STEP 11. Check the power supply circuit to the hands free module. Measure the voltage at hands free module connector C-35.





(1)Disconnect hands free module connector C-35, and measure the voltage available at the hands free module side of the connector.
(2)Ignition switch "ACC" position.





(3)Measure the voltage between terminal 1 and ground.
OK: The voltage should measure approximately 12 volts (battery positive voltage).

Q. Is the measured voltage approximately 12 volts (battery positive voltage)?

YES Go to Step 13.

NO Go to Step 12.

STEP 12. Check the wiring harness between hands free module connector C-35 (terminal 1) and ignition switch (ACC).





- Check the wiring harness for open circuit and short circuit.





NOTE:
Also check intermediate connector C-24 and joint connector C-01 for loose, corroded, or damaged terminals, or terminals pushed back in the connector. If intermediate connector C-24 and joint connector C-01 is damaged, repair or replace the connector as described in Harness Connector Inspection.

Q. Is the wiring harness between hands free module connector C-35 (terminal 1) and ignition switch (ACC) in good condition?

YES Refer to ignition switch diagnosis Inspection Procedure.

NO The wiring harness may be damaged or the connector(s) may have loose, corroded or damaged terminals, or terminals pushed back in the connector. Repair the wiring harness as necessary.

STEP 13. Check the ground circuit to the hands free module. Measure the resistance at hands free module connector C-35.





(1)Disconnect hands free module connector C-35, and measure at the wiring harness side.





(2)Measure resistance between terminal 15 and ground.
OK: The resistance should be 2 ohm or less.

Q. Is the measured resistance 2 ohms or less?

YES Go to Step 15.

NO Go to Step 14.

STEP 14. Check the wiring harness between hands free module connector C-35 (terminal 15) and ground.





- Check the ground wire for open circuit.





NOTE:
Also check joint connector C-01 for loose, corroded, or damaged terminals, or terminals pushed back in the connector. If joint connector C-01 is damaged, repair or replace the connector as described in Harness Connector Inspection.

Q. Is the wiring harness between hands-free module connector C-35 (terminal 15) and ground in good condition?

YES The trouble can be an intermittent malfunction How to Cope With Intermittent Malfunctions).

NO The wiring harness may be damaged or the connector(s) may have loose, corroded or damaged terminals, or terminals pushed back in the connector. Repair the wiring harness as necessary.

STEP 15. Temporarily replace the hands free module, and check the trouble symptom.

Check that the normal conversation is possible with the hands free cellular phone system.

Q. Is the normal conversation possible with the hands free cellular phone system?

YES Replace the hands free module.
NO Replace the radio and CD player or radio, CD player and CD changer.