Before replacing the ECU, ensure that the power supply circuit, the ground circuit and the communication circuit are normal.
TECHNICAL DESCRIPTION (COMMENT)
If the hazard warning lights do not illuminate, the hazard warning light switch input circuit in center panel unit or the ETACS-ECU may have a problem.
TROUBLESHOOTING HINTS
The center panel unit 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
STEP 1. Check that the turn-signal lights operate.
Check that the turn-signal lights illuminate normally.
Is the check result normal?
Go to Step 2.
Diagnose the turn-signal light. Refer to Inspection Procedure 1 "None of the turn-signal lights illuminate" .
STEP 2. Using scan tool (M.U.T.-IIISE), check data list.
Check the ETACS-ECU data list.
(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) Check the hazard warning light signal.
Turn ON the hazard light switch.
Item No.
Item name
Normal condition
89
Hazard switch
ON
Item No.
Item name
Normal condition
89
Hazard switch
ON
OK: Normal condition is displayed.
Is the check result normal?
Go to Step 3.
Troubleshoot the ETACS-ECU. Refer to Inspection Procedure 10 "The hazard warning light switch signal is not received" .
STEP 3. Retest the system.
Check that the hazard warning lights illuminate 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 ).