Step 1. ECU check by using the SWS monitor

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

• Ignition switch: OFF

ECU TO BE CHECKED

• ETACS ECU

• COLUMN ECU

OK: "OK" are displayed for all the items

Q: Is the check result normal?

"OK" are displayed for all the items:  Go to Step 2.
"NG" is displayed on the "ETACS ECU" menu.:  Refer to Inspection Procedure A-3 "Communication with ETACS-ECU is not possible ."
"NG" is displayed on the "COLUMN ECU" menu.:  Refer to Inspection Procedure A-2 "Communication with column switch (column-ECU) is not possible ."

Step 2. Function diagnosis by using the SWS monitor

Check the SWS communication signal, which are related to the lamp reminder function.

<Selected item> BUZZER - LGT MONI. ALRM

• Ignition switch: OFF (key removed)

• Lighting switch: HEAD

• Driver's door: open

Item No.	Item name	Normal condition
Item 00	HEADLAMP SW	ON when the lighting switch is at HEAD
Item 01	TAIL LAMP SW	ON when the lighting switch is at TAIL
Item 30	IG SW(IG1)	OFF
Item 32	DR DOOR SW*1	ON
	FRONT DOOR SW*2
Item 43	BUZZER	ON

NOTE: 

1. ^*1 : Except for Australia

2. ^*2 : Vehicles for Australia

OK: Normal conditions are displayed for all the items.

Q: Is the check result normal?

Normal conditions displayed for all the items:  Go to Step 3.
Normal condition is not displayed for item No.00 or No.01:  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 ."
Normal condition is not displayed for item No.32:  Refer to Inspection Procedure P-4 "The driver's door switch signal is not received <LH drive vehicles>." Refer to Inspection Procedure P-4 "The driver's door switch signal is not received <RH drive vehicles>."
Normal condition is not displayed for item No.43:  Replace the ETACS-ECU.

Step 3. Retest the system.

The lamp reminder buzzer function should work 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 ETACS-ECU.