Inspection Procedure A-1: Keyless Entry System does not Work.


caution Whenever the ECU is replaced, ensure that the input and output signal circuits are normal.


COMMENTS ON TROUBLE SYMPTOM
If the keyless entry system does not work normally, the input signal circuits to the components below or the ETACS-ECU may be defective.

  • Key reminder switch
  • All of the door switches
  • Transmitter
  • Driver’s door lock actuator

PROBABLE CAUSES

  • Malfunction of the key reminder switch
  • Malfunction of the door switches
  • Malfunction of the transmitter
  • Malfunction of the driver’s door lock actuator
  • Malfunction of the ETACS-ECU
  • Damaged harness wires and connectors

DIAGNOSIS PROCEDURE

STEP 1. 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 2.
Refer to .

STEP 2. Check the power supply circuit.
When the ignition switch is turned to the LOCK (OFF) position, check if the hazard warning lamp illuminate.

Q. Is the check result normal?
Go to Step 3.
Refer to GROUP 54A, Inspection Procedure A-1 "Check the battery power supply circuit to the ETACS-ECU ."

STEP 3. M.U.T.-III data list
Check the input signals from the drive’s door switch, the passenger’s switch and the rear door switch <Double cab>.

  • Drive’s door: Close
  • Passenger’s door: Close
  • Rear door <Double cab>: Close
Item No.
 Item name
 Normal condition
19
 Driver’s door switch
 OFF
48
 Passenger’s door switch
 OFF
49
 Rear door switch
 OFF
OK: Normal conditions are displayed for all the items.

Q. Are the check result normal?
Go to Step 4.
The door switches signal are not received. : Refer to GROUP 54A, Inspection Procedure C-5 "One of the switch signals is not received ."

STEP 4. Pulse check
Check the input signals below which are related to the encrypted code of the keyless entry transmitter.
System switch
 Check condition
Transmitter button
 When the button is turned from off to on
Key reminder switch
 When the inserted ignition key is pulled out
OK: The M.U.T.-III sounds or the voltmeter needle fluctuates.

Q. Are the check result normal?
Go to Step 5.
The keyless entry transmitter button signal is not received. : Refer to .
The key reminder switch signal is not received. : Refer to .

STEP 5. Retest the system.
Check the keyless entry system works normally.

Q. Is the check result normal?
The trouble can be an intermittent malfunction (Refer to GROUP 00, How to use Troubleshooting/inspection Service Points - How to Cope with Intermittent Malfunction ).
Replace the ETACS-ECU.