Inspection Procedure 2: During the conversation with the hands-free system, the speaker’s voice cannot be heard by the other party.












FUNCTION


During the conversation with the hands-free system, the signal of speaker’s voice is transmitted from the microphone unit to the hands-free-ECU. Then the signal is transmitted from the hands-free-ECU to the cellular phone.

COMMENTS ON TROUBLE SYMPTOM


During the conversation with the hands-free system, if the speaker’s voice cannot be heard by the other party, the hands-free-ECU or microphone unit may be defective.

PROBABLE CAUSES



DIAGNOSIS PROCEDURE

STEP 1. Check the cellular phone.
Check that the cellular phone can be used normally as a unit.

Q. Is the check result normal?
Go to Step 2.
Repair or replace the cellular phone.

STEP 2. Connector check: C-122 hands-free-ECU connector, D-01 microphone unit connector

Q. Is the check result normal?
Go to Step 3.
Repair the defective connector.

STEP 3. Check the wiring harness between C-121 hands-free-ECU connector and D-01 microphone unit connector.
(1)Disconnect C-122 hands-free-ECU connector and D-01 microphone unit connector, and check the wiring harness.
note Prior to the wiring harness inspection, check C-40 intermediate connector, and repair if necessary.
(2)Check the wiring harness between C-122 hands-free-ECU connector terminal No.1 and D-01 microphone unit connector terminal No.22
(3)Check the wiring harness between C-122 hands-free-ECU connector terminal No.1 and D-01 microphone unit connector terminal No.23
(4)Check the wiring harness between C-122 hands-free-ECU connector terminal No.2 and D-01 microphone unit connector terminal No.24

Q. Is the check result normal?
Go to Step 4.
Repair the wiring harness.

STEP 4. Temporarily replace the microphone unit, and check the trouble symptom.
Check that the normal conversation is possible with the hands-free system.

Q. Is the check result normal?
Replace the microphone unit.
Replace the hands-free-ECU.