Inspection Procedure 1: Hands free cellular phone system does not work normally.


caution Before replacing the ECU, ensure that the power supply circuit, the earth circuit and the communication circuit are normal.
















FUNCTION



COMMENTS ON TROUBLE SYMPTOM



PROBABLE CAUSES



  • Malfunction of the hands free-ECU
  • Malfunction of the microphone unit
  • Malfunction of the steering voice-control switch
  • Malfunction of the radio and CD player <vehicles without MMCS> or multivision display <vehicles with MMCS>
  • Damaged harness wires and connectors

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 normally?
Go to Step 2.
Repair or replace the cellular phone.

STEP 2. Temporarily replace the cellular phone, and check the trouble symptom.
Temporarily register a separate Bluetooth™-supported cellular phone (refer to ), and check that the hands free cellular phone system operates normally.

Q. Is the check result normally?
Ask the customer to have the cellular phone repaired or replaced. Then, delete the temporarily registered cellular phone. Once the customer prepares the normally-working cellular phone, register the cellular phone to the hands free-ECU (Refer to ).
Go to Step 3.

STEP 3. M.U.T.-III CAN bus diagnostics
Use the M.U.T.-III to diagnose the CAN bus lines.

Q. Is the check result normal?
Go to Step 4.
Repair the CAN bus line.

STEP 4. Connector check: C-41 hands free-ECU connector

Q. Is the check result normal?
Go to Step 5.
Repair the defective connector.

STEP 5. Resistance measurement at C-41 hands free-ECU connector.
(1)Disconnect the connector, and measure at the wiring harness side.
(2)Check the continuity between C-41 hands free-ECU connector terminal No.15 and body earth.
OK: Continuity exists (2 Ω or less)

Q. Is the check result normal?
Go to Step 7.
Go to Step 6.

STEP 6. Check the wiring harness between C-41 hands free-ECU connector terminal No.15 and body earth.

  • Check the earth wires for open circuit.

Q. Is the check result normal?
The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to use Troubleshooting/inspection Service Points - How to Cope with Intermittent Malfunction ).
Repair the wiring harness.

STEP 7. Voltage measurement at C-41 hands free-ECU connector.
(1)Disconnect the connector, and measure at the wiring harness side.
(2)Measure the voltage between terminal No.13 and body earth.
OK: System voltage

Q. Is the check result normal?
Go to Step 9.
Go to Step 8.

STEP 8. Check the wiring harness between C-41 hands free-ECU connector terminal No.13 and fusible link (36) <PETROL> or (38) <DIESEL>.

  • Check the power supply line for open circuit and short circuit.
note Prior to the wiring harness inspection, check ETACS-ECU connector C-307 and C-317, and repair if necessary.

Q. Is the check result normal?
The trouble can be an intermittent malfunction (Refer to GROUP 00, How to use Troubleshooting/inspection Service Points, How to Cope with Intermittent Malfunction ).
Repair the wiring harness.

STEP 9. Connector check: D-04 microphone unit connector

Q. Is the check result normal?
Go to Step 10.
Repair the defective connector.

STEP 10. Check the wiring harness between C-41 hands free-ECU connector and D-04 microphone unit connector.

  • Check the communication lines for open or short circuit.
(1)Disconnect C-41 hands free-ECU connector and D-04 microphone unit connector, and check the wiring harness.
note Prior to the wiring harness inspection, check intermediate connector C-130 and joint connector C-46 <RHD>, and repair if necessary.
(2)Check the wiring harness between C-41 hands free-ECU connector terminal No.23 and D-04 microphone unit connector terminal No.1
(3)Check the wiring harness between C-41 hands free-ECU connector terminal No.24 and D-04 microphone unit connector terminal No.2

Q. Is the check result normal?
Go to Step 11.
Repair the wiring harness.

STEP 11. Connector check: C-105 radio and CD player connector <vehicles without MMCS and audio amplifier> or C-142 multivision display connector <vehicles with MMCS and audio amplifier>

Q. Is the check result normal?
Go to Step 12.
Repair the defective connector.

STEP 12. Check the wiring harness between C-41 hands free-ECU connector and C-105 radio and CD player connector <vehicles without MMCS> or C-142 multivision display connector <vehicles with MMCS>.
(1)Disconnect C-41 hands free-ECU connector and C-105 radio and CD player connector <vehicles without MMCS> or C-142 multivision display connector <vehicles with MMCS>, and check the wiring harness.

  • Check the communication lines for open or short circuit.
note Prior to the wiring harness inspection, check C-140 intermediate connector, and repair if necessary. <vehicles with MMCS>
(2)Check the wiring harness between C-41 hands free-ECU connector terminal No.9 and C-105 radio and CD player connector terminal No.3 <vehicles without MMCS>
(3)Check the wiring harness between C-41 hands free-ECU connector terminal No.21 and C-105 radio and CD player connector terminal No.2 <vehicles without MMCS>
(4)Check the wiring harness between C-41 hands free-ECU connector terminal No.9 and C-142 multivision display connector terminal No.45 <vehicles with MMCS>
note Prior to the wiring harness inspection, check intermediate connector C-140, and repair if necessary. <vehicles with MMCS>
(5)Check the wiring harness between C-41 hands free-ECU connector terminal No.21 and C-142 multivision display connector terminal No.46 <vehicles with MMCS>
note Prior to the wiring harness inspection, check intermediate connector C-140, and repair if necessary. <vehicles with MMCS>

Q. Is the check result normal?
Go to Step 13.
Repair the wiring harness.

STEP 13. Temporarily replace the microphone unit, and check the trouble symptom.
Check that the normal conversation is possible with the hands free cellular phone system.

Q. Is the check result normal?
Replace the microphone unit.
Go to Step 14.

STEP 14. Temporarily replace the hands free-ECU, and check the trouble symptom.
Check that the normal conversation is possible with the hands free cellular phone system.

Q. Is the check result normal?
Replace the hands free-ECU.
Replace the radio and CD player <vehicles without MMCS> or multivision display <vehicles with MMCS>.