Inspection Procedure 7
This document has been updated per Mitsubishi TSB #07-54-005Inspection Procedure 7: Check the hands-free-ECU power supply circuit.
CAUTION: Before replacing the ECU, ensure that the power supply circuit, the ground circuit and the communication circuit are normal.
Hands Free Module Power Supply Circuit:
CIRCUIT OPERATION
- The power supply to the hands-free module is provided by the fusible link (36).
- If the power supply system from the battery is defective, the system operates by the power supply from the ignition switch (IG1).
TECHNICAL DESCRIPTION (COMMENT)
If the hands-free cellular phone system don't work, power supply and ground system to the hands-free module, or the hands-free module itself may be defective.
TROUBLESHOOTING HINTS
- The wiring harness or connectors may have loose, corroded, or damaged terminals, or terminals pushed back in the connector
- The hands-free module may be defective
DIAGNOSIS
Required Special Tools:
- MB991223: Harness Set
- MB992006: Extra Fine Probe
STEP 1. Check hands-free module connector C-110 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Q: Is hands-free module connector C-110 in good condition?
YES : Go to Step 2.
NO : Repair or replace the damaged component (Refer to general (electrical), Harness Connector Inspection).
STEP 2. Check the ground circuit to the hands-free module. Measure the resistance at hands-free module connector C-110.
1. Disconnect hands-free module connector C-110, and measure at the wiring harness side.
2. Measure the resistance value between terminal 15 and ground.
OK: The resistance should be 2 ohms or less.
Q: Is the measured resistance 2 ohms or less?
YES : Go to Step 4.
NO : Go to Step 3.
STEP 3. Check the wiring harness between hands-free module connector C-110 (terminal 15) and ground.
Q: Is the wiring harness between hands-free module connector C-110 (terminal 15) and ground in good condition?
YES : Replace the hands-free module. The system should communicate with the hands-free module normally.
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 the wiring harness between hands-free module connector C-110 (terminal 13) and fusible link (36).
NOTE: Also check ETACS-ECU connectors C-307 and C-317 for loose, corroded, or damaged terminals, or terminals pushed back in the connector. If ETACS-ECU connector C-307 or C-317 is damaged, repair or replace the damaged component(s) as described in general (electrical), Harness Connector Inspection.
Q: Is the wiring harness between hands-free module connector C-110 (terminal 13) and fusible link (36) in good condition?
YES : Replace the hands-free module. The system should communicate with the hands-free module normally.
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.
ERASE THE PASSCODE
The 4-digit passcode set by security function can be erased by operating the hang-up switch.
1. Turn the ignition switch to the "ON" or "ACC" position, and check if the radio and CD player or CD changer or the audio visual navigation unit is activated.
2. Check that the hands free cellular phone system is not in voice recognition mode.
3. Press and hold the hang-up switch for approximately 2 seconds (1.5 seconds or more).
4. Within approximately 10 seconds after performing step 3, press and hold the hang-up switch for approximately 2 seconds (1.5 seconds or more) twice again.
NOTE: Even if the passcode is erased, guidance such as voice guide is not provided.
5. After the operation, check if the lock with the passcode is unlocked. If the lock is not unlocked, repeat from step 2.