Inspection Procedure 1: The ignition key cylinder illumination light does not illuminate/extinguish normally.
caution
Before replacing the ECU, ensure that the power supply circuit, the ground circuit and the communication circuit are normal.
When the ETACS-ECU of vehicles without KOS is replaced, the encrypted code of the ignition key needs to be registered to the ETACS-ECU (If the encrypted code is not registered, the engine cannot be started. Register the encrypted code as described in Immobilizer System - How to Register Key ID .).
OPERATION
The ETACS-ECU operates this function in accordance with the input signals below.
Ignition switch (IG1)
Key reminder switch
Door switches
Driver's door lock actuator
TECHNICAL DESCRIPTION (COMMENT)
If this function does not work normally, these input signal circuit(s), the ignition key cylinder illumination light or the ETACS-ECU may be defective.
TROUBLESHOOTING HINTS
The key reminder switch may be defective
The driver's door switch may be defective
The driver's door lock actuator may be defective
The ignition key cylinder illumination light bulb may be defective
The ETACS-ECU may be defective
The wiring harness or connectors may have loose, corroded, or damaged terminals, or terminals pushed back in the connector
DIAGNOSIS
Required Special Tools:
MB992006: Extra fine probe
MB991223: Harness set
STEP 1. Using scan tool (M.U.T.-IIISE), read the DTC.
(1)
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 Scan tool (M.U.T.-IIISE) ."
(2) Turn the ignition switch to the "ON" position.
(3) Check whether the ETACS-ECU related DTC is set.
(4) Turn the ignition switch to the "LOCK" (OFF) position.
Is the DTC set?
Troubleshoot the ETACS-ECU. Refer to .
Go to Step 2.
STEP 2. Check the interior lights operation.
Check that the interior lights illuminate normally.
Is the check result normal?
Go to Step 3.
Troubleshoot the interior light. Refer to .
STEP 3. Check of open circuit in LP+3 and RLP- lines between key reminder switch connector and ETACS-ECU connector.
Is the check result normal?
Go to Step 4.
Repair the connector(s) or wiring harness.
STEP 4. Check of ignition key cylinder illumination light bulb.
Check that the ignition key cylinder illumination light bulb is normal.
Is the check result normal?
Go to Step 5.
Replace the bulb of the ignition key cylinder illumination light.
STEP 5. Retest the system.
Check that the ignition key cylinder illumination light illuminates/extinguishes normally.
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 ).