INSPECTION PROCEDURE 5: Keyless Entry System does not Work.


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

OPERATION
The lock/unlock signals from the transmitter are received by WCM, and then sent to ETACS-ECU from WCM. When ETACS-ECU receives signals from the key reminder switch and all the door switches, ETACS-ECU actuates the keyless entry system.

PROBABLE CAUSES

  • Malfunction of the key reminder switch
  • Malfunction of the door switches
  • Malfunction of keyless entry transmitter
  • Malfunction of the WCM
  • Malfunction of ETACS-ECU
  • Damaged wiring harness and connectors
  • Option coding information

DIAGNOSTIC PROCEDURE

STEP 1. ETACS-ECU coding data check
(1)Use M.U.T.-III to read out the option coding information in ETACS-ECU (Refer to GROUP 00 - Precautions before Service - Coding List ).
(2)Check if the "Keyless function" is "Enabled."

Q. Is the check result normal?
Go to Step 2.
Operate the M.U.T.-III to set the option coding "keyless" to "enabled," and check the trouble symptom.

STEP 2. M.U.T.-III CAN bus diagnostics
Use M.U.T.-III to diagnose the CAN bus lines.

Q. Is the CAN bus normal?
Go to Step 3.
Repair the CAN bus line (Refer to GROUP 54C - Troubleshooting ).

STEP 3. M.U.T.-III diagnosis code
Check that ETACS-ECU sets a diagnosis code.

Q. Is the diagnosis code set?
Refer to .
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 lamp

Q. Is the check result normal?
Go to Step 5.
Refer to GROUP 54A - 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?
Go to Step 6.
Refer to GROUP 42A - Troubleshooting .

STEP 6. M.U.T.-III 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 tailgate.
Item No.
 Item name
 Normal conditions
Item 256
 Dr door ajar switch
 Close
Item 257
 As door ajar switch
 Close
Item 258
 RR door ajar switch
 Close
Item 259
 RL door ajar switch
 Close
Item 260
 Trunk/gate trunk ajar switch
 Close
Item 264
 Handle lock switch
 Key in → Key out
OK: Normal conditions are displayed for all the items.

Q. Are the check result normal?
Normal conditions are displayed for all the items. : Go to Step 7.
Normal condition is not displayed for item No. 256. : Refer to GROUP 54A - inspection procedure 5: front door switch (driver’s side) signal is not received .
Normal condition is not displayed for item No. 257. : Refer to GROUP 54A - inspection procedure 6: front door switch (passenger’s side) signal is not received .
Normal condition is not displayed for item No. 258. : Refer to GROUP 54A - Inspection procedure 7: rear door switch (RH) signal is not received .
Normal condition is not displayed for item No. 259. : Refer to GROUP 54A - inspection procedure 8: rear door switch (LH) signal is not received .
Normal condition is not displayed for item No. 260. : Refer to GROUP 54A - inspection procedure 9: tailgate latch signal is not received .
Normal condition is not displayed for item No. 264. : Refer to GROUP 54A - inspection procedure 3: key reminder switch signal is not received .

STEP 7. Pulse check
Check for the WCM signals related to the keyless entry system.
Item name
 Conditions
Transmitter switch
 Turn the switch ON/OFF.
OK: The M.U.T.-III buzzer sounds.

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

STEP 8. Retest the system.
Check if the keyless entry system works normally.

Q. Is the check result normal?
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction )
Replace WCM and register the ID codes (Refer to ).