Step 1. ECU check on the SWS monitor

Check that the power supply and earth lines to the column switch (column-ECU) and the front-ECU and the SWS communication lines are normal.

• Ignition switch: OFF

ECUS TO BE CHECKED

• COLUMN ECU

• FRONT ECU

OK: "OK" are displayed for all the items

Q: Are the check result normal?

"OK" are displayed for all the items:  Go to Step 2.
"NG" is displayed on the "COLUMN ECU" menu.:  Refer to Inspection Procedure A-2 "Communication with the column switch (column-ECU) is not possible" .
"NG" is displayed on the "FRONT ECU" menu.:  Refer to Inspection Procedure A-4 "Communication with the front-ECU is not possible" .

Step 2. Function diagnosis by using the SWS monitor

Check the SWS communication signal, which are related to the high-beam headlamps.

<Selected item> LIGHTING - HEADLAMP HI

• Ignition switch: ON

• Lighting switch: HEAD

• Dimmer switch: from OFF to ON, and then to OFF again

Item No.	Item name	Normal conditions
Item 00	HEADLAMP SW	ON
Item 02	DIMMER SW	from OFF to ON, and then to OFF again ("ON" should be displayed when the dimmer switch is operated)
Item 03	PASSING SW	OFF
Item 30	IG SW(IG1)	ON

OK: Normal conditions displayed for all the items

Q: Are the check result normal?

Normal conditions are displayed for all the items.:  Go to Step 3.
Normal condition is not displayed for item 00, 02 or 03.:  Refer to inspection procedure P-5 "The column switch (lighting and turn-signal lamp switch) signal is not received" .
Normal condition is not displayed for item No.30.:  Refer to inspection procedure P-2 "The ignition switch (IG1) signal is not received" .

Step 3. Retest the system.

Check that the high-beam headlamps illuminate normally.

Q: Is the check result normal?

YES:  The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to Cope with Intermittent Malfunction ).
NO:  Replace the front-ECU.