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Inspection Procedure 8: Keyless entry function does not work
 
 
cautionBefore replacing the ECU, ensure that the power supply circuit, the ground circuit and the communication circuit are normal.
 
 
 
 
TECHNICAL DESCRIPTION (COMMENT)
The ETACS-ECU operates the keyless entry function according to the signals of all door switches and the lock/unlock signal of the keyless operation key which is sent through the KOS&OSS-ECU.
 
 
TROUBLESHOOTING HINTS
  • Malfunction of CAN bus line
  • Malfunction of the door switches
  • Malfunction of the keyless operation key
  • Damaged wiring harness and connectors
  • Malfunction of the KOS&OSS-ECU
  • Malfunction of ETACS-ECU
 
 
DIAGNOSIS
STEP 3. ETACS-ECU coding data check.
(1)
cautionTo prevent damage to scan tool (M.U.T.-III), always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool (M.U.T.-III).
Connect scan tool (M.U.T.-III) [Refer to "How to connect scan tool (M.U.T.-III) "].
(2) Turn the power supply mode of the engine switch to "ON".
(3) Read out the option coding information in the ETACS-ECU (Refer to GROUP 00, Precautions before service, Coding Table ).
(4) Check that the "Keyless entry" is set to "YES."
(5) Turn the power supply mode of the engine switch to "OFF".
Is the ETACS-ECU coding data normal?
Go to Step 2.
Operate scan tool (M.U.T.-III) to set the option coding "Keyless entry" to "Yes," and check the trouble symptom.
 
STEP 2. Using scan tool (M.U.T.-III), diagnose the CAN bus line.
(1)
cautionTo prevent damage to scan tool (M.U.T.-III), always turn the power supply mode of the engine switch to the "OFF" position before connecting or disconnecting scan tool (M.U.T.-III).
Connect scan tool (M.U.T.-III) [Refer to "How to connect scan tool (M.U.T.-III) "].
(2) Turn the power supply mode of the engine switch to "ON".
(3) Diagnose the CAN bus line.
(4) Turn the power supply mode of the engine switch to "OFF".
Is the CAN bus line found to be normal?
Go to Step 3.
Repair the CAN bus line (Refer to GROUP 54C, Diagnosis ).
 
STEP 3. Using scan tool (M.U.T.-III), read the diagnostic trouble code.
Check if any DTC is set in the KOS&OSS-ECU.
(1)
cautionTo prevent damage to scan tool (M.U.T.-III), always turn the power supply mode of the engine switch to the "OFF" position before connecting or disconnecting scan tool (M.U.T.-III).
Connect scan tool (M.U.T.-III) [Refer to "How to connect scan tool (M.U.T.-III) "].
(2) Turn the power supply mode of the engine switch to "ON".
(3) Check if DTC is set.
(4) Turn the power supply mode of the engine switch to "OFF".
Is the DTC set?
Refer to diagnostic trouble code chart .
Go to Step 4.
 
STEP 4. Check the power supply system
With the engine switch in the LOCK (OFF) position, check if the following function operates normally:
  • Hazard warning light
Is the check result normal?
Go to Step 5.
Refer to GROUP 54A - ETACS, Power Supply Circuit .
 
STEP 5. Check the operation of the central door locking system.
Check that the central door locking system works normally.
Is the check result normal?
Go to Step 6.
Refer to GROUP 42A, Troubleshooting .
 
STEP 6. Using scan tool (M.U.T.-III), check data list.
Check the signals related to the keyless entry function operation.
(1)
cautionTo prevent damage to scan tool (M.U.T.-III), always turn the power supply mode of the engine switch to the "OFF" position before connecting or disconnecting scan tool (M.U.T.-III).
Connect scan tool (M.U.T.-III) [Refer to "How to connect the Scan Tool (M.U.T.-III) "].
(2) Turn the power supply mode of the engine switch to "OFF".
(3) Check the ETACS-ECU service data relevant to the operation of keyless entry function.
(1) Open the driver's door or front passenger's door.
 
Item No.Item nameNormal condition
19Driver's door switchON
48Passenger’s door switchON
(2) Open the rear door (RH) after the all doors.
 
Item No.Item nameNormal condition
49Rear door switchON
(3) Open the rear door (LH) after the all doors.
 
Item No.Item nameNormal condition
49Rear door switchON
OK: Normal condition are displayed.
Is the check result normal?
Go to Step 7.
Perform troubleshooting for the ETACS-ECU (Refer to GROUP 54A, ETACS, Troubleshooting ).
 
STEP 7. Check with another registered keyless operation key.
Check that the keyless entry function can be used with another keyless operation key.
Can the keyless entry function be used?
Replace the keyless operation key concerned and register the ID codes (Refer to ).
Go to Step 8.
 
STEP 8. Check of the troubles
Replace ETACS-ECU. After the replacement, perform the coding, and check that the keyless entry function operates normally.
Is the check result normal?
Intermittent malfunction is suspected (Refer to GROUP 00, How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction ).
Replace KOS&OSS-ECU and register the ID codes (Refer to ).