Inspection Procedure 12

Inspection Procedure 12: Front passenger's door unlock sensor does not work.

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

Unlock Sensor (Front Passenger's Side) Circuit (Part 1):

Unlock Sensor (Front Passenger's Side) Circuit (Part 2):

TROUBLESHOOTING HINTS
- Malfunction of the outside transmission antenna assembly (passenger's side)
- Malfunction of the unlock switch (front passenger's side)
- Damaged wiring harness and connectors
- Malfunction of the KOS-ECU

DIAGNOSIS

Required Special Tools:
- MB992006: Extra fine probe
- MB991223: Harness set
- MB991958: Scan Tool (M.U.T.-III Sub Assembly)
- MB991824: Vehicles Communication Interface (V.C.I.)
- MB991827: M.U.T.-III USB Cable
- MB991910: M.U.T.-III Main Harness A

STEP 1. Using scan tool MB991958, read the diagnostic trouble code.

CAUTION: To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991958.







1. Connect scan tool MB991958. Refer to "How to connect scan tool (M.U.T.-III)." How To Connect The Scan Tool (M.U.T.-III)
2. Turn the ignition switch to the "ON" position.
3. Check whether the KOS-ECU related DTC is set.
4. Turn the ignition switch to the "LOCK" (OFF) position.

Q : Is the DTC set?

YES : Diagnose the KOS-ECU. Diagnostic Trouble Code Descriptions

NO : Go to Step 2.

STEP 2. Check KOS-ECU connector C-31 and unlock sensor (front passenger's side) connector E-05 for loose, corroded or damaged terminals, or terminals pushed back in the connector.

Q : Are KOS-ECU connector C-31 and unlock sensor (front passenger's side) connector E-05 in good condition?

YES : Go to Step 3.

NO : Repair or replace the damaged component(s). Check that the passenger's door unlock sensor works normally.

STEP 3. Check the wiring harness between KOS-ECU connector C-31 (terminal Nos. 25 and 36) and unlock sensor (front passenger's side) connector E-05 (terminal Nos. 4 and 2), and between unlock sensor (front passenger's side) connector E-05 (terminal No. 6) and ground.

- Check the signal and ground wires for open circuit.

NOTE: Also check joint connector (1) C-03, intermediate connectors C-114, C-115 for loose, corroded, or damaged terminals, or terminals pushed back in the connector. If joint connector (1) C-03, intermediate connectors C-114, C-115 is damaged, repair or replace the damaged component(s).

Q : Are the wiring harness between KOS-ECU connector C-31 (terminal Nos. 25 and 36) and unlock sensor (front passenger's side) connector E-05 (terminal Nos. 4 and 2), and between unlock sensor (front passenger's side) connector E-05 (terminal No. 6) and ground 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. Check that the passenger's door unlock sensor works normally.

STEP 4. KOS communication test

Using scan tool (M.U.T-III), perform the antenna communication test to check that the outside transmission antenna assembly (passenger's side) communicates normally.

Q : Is the check result normal?

YES : Go to Step 5.

NO : Perform troubleshooting for DTC No. B240B. B240B

STEP 5. Check of the troubles

Operate the unlock sensor (front passenger's side) and check that the door can be locked.

Q : Is the check result normal?

YES : The diagnosis is complete.

NO : Replace KOS-ECU and register the ID codes. ID Codes Registration Judgement Table