Inspection Procedure G-1: The turn-signal lamps do not illuminate.


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


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 be defective. Alternatively, there are cases where fail-safe function is activated by the following diagnosis codes set in the ETACS-ECU.
Diagnosis code No.
 Fail-safe operation
B1740, B1741
 Either of right and left side turn-signal lamps start flashing faster.
B1742
 Both turn-signal lamps start flashing faster.
B1743
 All turn-signal lamps (including the indicator) do not illuminate.

PROBABLE CAUSES



DIAGNOSIS PROCEDURE


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


Check that ETACS-ECU sets a diagnosis code.

Q. Is the diagnosis code set?

Refer to diagnosis code chart .

Go to Step 2.

STEP 2. M.U.T.-III actuator test


Perform the actuator test for the ETACS-ECU, and check that the turn-signal lamps illuminate normally.

Q. Is the check result normal?

Go to Step 3.

Go to Step 4.

STEP 3. M.U.T.-III data list


Check the input signal from the ignition switch (IG1) and turn-signal lamp switch.

Item No.
 Item name
 Normal condition
30
 Ignition Switch (IG1)
 OFF

Item No.
 Item name
 Normal condition
06
 Turn signal lamp switch(LH)
 ON
07
 Turn signal lamp switch(RH)
 OFF

Item No.
 Item name
 Normal condition
06
 Turn signal lamp switch(LH)
 OFF
07
 Turn signal lamp switch(RH)
 ON
OK: Normal conditions are displayed for all the items.

Q. Is the check result normal?

YES <All the signals are received normally.> : Go to Step 4.

NO <The ignition switch (IG1) signal is not received.> : Refer to inspection procedure J-3 "The ignition switch (IG1) signal is not received ."

NO <The turn-signal lamp switch signal is not received.> : Refer to Inspection Procedure J-1 "The column switch (lighting and wiper switch) signal is not received ."

STEP 4. Retest the system.


Check that the turn-signal lamps illuminate 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. Then perform the variant coding and write the VIN data (Refer to GROUP 00, Precautions Before Service - How to Perform Variant Coding ).