Inspection Procedure 6: The Headlamp Automatic-shutdown Function does not Work Normally.


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


COMMENTS ON TROUBLE SYMPTOM


The ETACS-ECU operates this function in accordance with the input signals below.

If this function does not work normally, these input signal circuit(s), the front-ECU or the ETACS-ECU may be defective. Note that this function can be disabled/enabled by the adjustment function (default setting; enabled).

PROBABLE CAUSES



DIAGNOSIS PROCEDURE


STEP 1. Check that the headlamps operate.


Check that the low-beam and high-beam headlamps work normally.

Q. Is the check result normal?

Go to Step 2.

Repair the headlamps. Refer to trouble symptom chart .

STEP 2. Pulse check


Check the input signals below, which are related to the headlamp automatic-shutdown function.
System switch
 Check condition
Ignition switch (IG1)
 When turned from ACC to ON
Driver’s door switch
 When the driver’s door is opened
Headlamp switch
 When the lighting switch is turned to the HEAD position
OK: The M.U.T.-III sounds or the voltmeter needle fluctuates.

Q. Is the check result normal?

YES (All the signals are received normally) : Go to Step 3.

NO (The ignition switch (IG1) signal is not received) : Refer to ETACS - Input Signal Chart .

NO (The driver’s door switch signal is not received) : Refer to ETACS - Input Signal Chart .

NO (The headlamp switch signal is not received) : Refer to ETACS - Input Signal Chart .

STEP 3. Check the SWS monitor customized function.


Check that the headlamp automatic-shutdown function has been enabled by using the customized function.
caution The SWS monitor must be used in order to confirm and change that setting. Use the SWS monitor to confirm and/or change the customized function.

Q. Is the check result normal?

Go to Step 4.

Enable the headlamp automatic-shutdown function by using the customized function (Refer to Customize Function ).

STEP 4. Retest the system.


Replace the ETACS-ECU, and then check that the headlamp automatic-shutdown function works normally.
(1)Replace the ETACS-ECU.
(2)Check that the headlamp automatic-shutdown function works normally.

Q. Is the check result normal?

The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to Cope with Intermittent Malfunction ).

Replace the front-ECU.