Inspection Procedure 5 [Vehicles With Radio and CD Player]

Inspection Procedure 5: DIAGNOSIS MODE cannot be made an entry. [Vehicles with radio and CD player]

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










TECHNICAL DESCRIPTION (COMMENT)

If the diagnosis mode cannot be made an entry, the hands free module, the communication between the hands free module, and the radio and CD player, or the power supply system of hands free module may have a problem.

TROUBLESHOOTING HINTS

- The hands free module may be defective.
- The radio and CD player may be defective.
- The wiring harness or connectors may have loose, corroded, or damaged terminals, or terminals pushed back in the connector.

DIAGNOSIS

Required Special Tools:

- MB991223: Harness Set
- MB992006: Extra Fine Probe

STEP 1. Check the radio and CD player operation.

Check if the radio and CD player work normally and the sound is output.

Q. Is the check result normal?

YES Go to Step 2.
NO Troubleshoot the radio and CD player. (Refer to Symptom Chart.)
STEP 2. Check hands free module connector C-11 and radio and CD player connector C-109 for loose, corroded or damaged terminals, or terminals pushed back in the connector

Q. Are hands free module connector C-11 and radio and CD player connector C-109 in good condition?

YES Go to Step 3.
NO Repair or replace the damaged component(s). Harness Connector Inspection.
STEP 3. Check the wiring harness between hands free module connector C-11 (terminal 2, 16) and radio and CD player connector C-109 (terminal 1, 10).

- Check the signal lines for open circuit and short circuit.

Q. Is the wiring harness between hands free module connector C-11 (terminal 2, 16) and radio and CD player connector C-109 (terminal 1, 10) in good condition?

YES Go to step 4.
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 4. Check if the power supply circuit of hands free ECU have a problem.

Perform the inspection Procedure 1 "Check the hands free module power supply circuit."
of the troubleshooting. (Refer to Inspection Procedure 1.)

Q. Is the check result normal?

YES Go to step 5.
NO Repair according to the troubleshooting for reference.
STEP 5. Replace the hands free module temporarily, and check the trouble symptom.

Q. Is the check result normal?

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