Inspection Procedure 1: Keyless Entry System Does Not Work: Diagnosis
Required Special Tools:
- MB991223: Harness Set
- MB992006: Extra Fine Probe
- STEP 1. ETACS-ECU coding data check
- Use scan tool (M.U.T-IIISE) to read out the option coding information in ETACS-ECU.
- Check if the "Keyless function" is "Enabled."
Q: Is the check result normal?
YES : Go to Step 2.
NO : Operate the scan tool (M.U.T-IIISE) to set the option coding "keyless" to "enabled," and check the trouble symptom.
- STEP 2. Using scan tool (M.U.T-IIISE), diagnose the CAN bus line. CAUTION: To prevent damage to scan tool (M.U.T.-IIISE), always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool (M.U.T.-IIISE).
- Connect scan tool (M.U.T-IIISE). Refer to "HOW TO CONNECT THE SCAN TOOL (M.U.T-IIISE) ."
- Turn the ignition switch to the "ON" position.
- Diagnose the CAN bus line.
- Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the CAN bus line found to be normal?
YES : Go to Step 3.
NO : Repair the CAN bus line. (Refer to DIAGNOSIS ).
- STEP 3. Using scan tool (M.U.T.-IIISE), read the DTC.
Check whether the ETACS-ECU sets a DTC.
Q: Is the DTC set?
YES : Refer to KEYLESS ENTRY SYSTEM DIAGNOSIS .
NO : Go to Step 4.
- STEP 4. Check the power supply system
With the ignition switch in the "LOCK" (OFF) position, check if the following function operates normally:
- Hazard warning light
Q: Is the check result normal?
YES : Go to Step 5.
NO : Refer to MALFUNCTION OF ETACS-ECU POWER SUPPLY CIRCUIT .
- STEP 5. Check the operation of the central door locking system.
Check that the central door locking system works normally.
Q: Is the check result normal?
YES : Go to Step 6.
NO : Refer to TROUBLESHOOTING .
- STEP 6. Using scan tool (M.U.T.-IIISE), check data list.
Check for the signals related to the keyless entry system operation.
- Turn the ignition switch to the "LOCK" (OFF) position.
- Remove the ignition key from the ignition key cylinder.
- Close the driver's door.
- Close the front passenger's doors.
- Close the RH-side rear door.
- Close the LH-side rear door.
- Close the liftgate
Item No. Item name Normal condition 81 Dr door ajar switch Close 82 As door ajar switch Close 83 RR door ajar switch Close 84 RL door ajar switch Close 85 Trunk/gate trunk ajar switch Close 88 Handle lock switch Key in → Key out OK: Normal conditions are displayed for all the items.
Q: Is the check result normal?
Normal conditions are displayed for all the items. : Go to Step 7.
Normal condition is not displayed for item No. 81. : Refer to INSPECTION PROCEDURE 5: "THE FRONT DOOR SWITCH (DRIVER'S SIDE) SIGNAL IS NOT RECEIVED ."
Normal condition is not displayed for item No. 82. : Refer to INSPECTION PROCEDURE 6: "THE FRONT DOOR SWITCH (PASSENGER'S SIDE) SIGNAL IS NOT RECEIVED ."
Normal condition is not displayed for item No. 83. : Refer to INSPECTION PROCEDURE 7: "THE REAR DOOR SWITCH (RH) SIGNAL IS NOT RECEIVED ."
Normal condition is not displayed for item No. 84. : Refer to INSPECTION PROCEDURE 8: "THE REAR DOOR SWITCH (LH) SIGNAL IS NOT RECEIVED ."
Normal condition is not displayed for item No. 85. : Refer to INSPECTION PROCEDURE 9: "THE LIFTGATE LOCK ACTUATOR SIGNAL IS NOT RECEIVED ."
Normal condition is not displayed for item No. 88. : Refer to INSPECTION PROCEDURE 3: "THE KEY REMINDER SWITCH SIGNAL IS NOT RECEIVED ."
- STEP 7. Check whether the transmitter battery is discharged.
The switch indicator should illuminate when you press the lock/unlock switch in the ignition key.
Q: Does the switch indicator illuminate when you press the switch?
YES : Go to Step 8
NO : Replace the transmitter battery.
- STEP 8. Replace the ignition key, and then check whether the DTC is set again.
Check if the keyless entry system works normally.
Q: Is the check result normal?
YES : The diagnosis is complete.
NO : Go to Step 9
- STEP 9. Check of short to power supply, short to ground, open circuit in WRA, WUHF, WPC, WGN line between ETACS-ECU connector and receiver antenna connector.
Q: Is the check result normal?
YES : Go to Step 10.
NO : Repair the connector(s) wiring harness.
- STEP 10. Retest the system.
Check if the keyless entry system works normally.
Q: Is the check result normal?
YES : Intermittent malfunction (Refer to HOW TO COPE WITH INTERMITTENT MALFUNCTION ).
NO : Replace receiver antenna (Refer to RECEIVER ANTENNA ) and turn ignition switch to ON and OFF. Then go to Step 11.
- STEP 11. Retest the system.
Check if the keyless entry system works normally.
Q: Is the check result normal?
YES : The diagnosis is complete.
NO : Replace ETACS-ECU and register the ID codes (Refer to KEYLESS ENTRY SYSTEM TIMER LOCK FUNCTION INSPECTION ).