Inspection Procedure 13: None of the turn-signal lamps illuminate.


caution
  • Before replacing the ECU, ensure that the power supply circuit, the earth 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 .)

COMMENTS ON TROUBLE SYMPTOM


If all the turn-signal lamps do not illuminate, the ignition switch (IG1), the turn-signal lamp switch input circuit or the ETACS-ECU may have a problem.

PROBABLE CAUSES



DIAGNOSIS PROCEDURE


STEP 1. M.U.T.-III diagnosis code


Check if diagnosis code is set to the ETACS-ECU.

Q. Is the diagnosis code set?

Troubleshoot the ETACS-ECU. Refer to .

Go to Step 2.

STEP 2. M.U.T.-III data list


Using the ETACS-ECU service data, check the signals related to the illumination of turn-signal lamp.

Item No.
 Item name
 Normal condition
Item 254
 IG voltage
 System voltage
Item 343
 Turn switch left
 ON

Item No.
 Item name
 Normal condition
Item 344
 Turn switch right
 ON
OK: Normal conditions are displayed for all the items.

Q. Is the check result normal?

Normal conditions are displayed for all the items. : Go to Step 3.

Normal condition is not displayed for item No. 254. : Troubleshoot the ETACS-ECU. Refer to Inspection Procedure 2 "The ignition switch (IG1) signal is not received" .

Normal condition is not displayed for item No. 343 or 344. : Troubleshoot the ETACS-ECU. Refer to Inspection Procedure 11 "The column switch signal is not received" .

STEP 3. Retest the system


Check that the turn-signal lamps illuminate.

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.