Inspection Procedure B-2

Tone Alarm: Light Reminder Tone Alarm Function Does Not Work Normally.

NOTE: This troubleshooting requires use of scan tool MB991502 and SWS monitor kit MB991862. For details of how to use the SWS monitor, refer to "How to use SWS monitor."

Light Reminder Tone Alarm Function:

CIRCUIT OPERATION
The ETACS-ECU operates the light reminder tone alarm function according to the following signals:
- Ignition switch (IG1): OFF
- Ignition key reminder switch: ON
- Driver's door switch: ON
- Taillight switch: ON
- Headlight switch: ON

The ETACS-ECU operates the light reminder tone alarm function under the following conditions:
- Ignition switch: "LOCK" (OFF) position
- Ignition key: Removed from the ignition key cylinder
- Driver's door: open
- Taillight or headlight: Illuminating

TECHNICAL DESCRIPTION (COMMENT)
If the function does not work normally, the input circuit system from the switches or the ETACS-ECU may be defective (refer to "CIRCUIT OPERATION").

TROUBLESHOOTING HINTS
- Malfunction of front door switches
- Malfunction of column switch (turn-signal light and lighting switch)
- Malfunction of the ETACS-ECU
- Damaged harness wires or connectors

DIAGNOSIS

Required Special Tools:
- MB991223: Test Harness Set
- MB991502: Scan Tool (MUT-II)
- MB991862: SWS Monitor Kit

STEP 1. Use scan tool to select "ECU COMM CHECK" on the SWS monitor display.
Check the following ECUs:
- ETACS-ECU
- Column

CAUTION: To prevent damage to scan tool MB991502, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991502. Also connect SWS monitor kit MB991862 after turning on scan tool MB991502.







1. Connect scan tool MB991502 to the data link connector.
2. Connect SWS monitor kit MB991862 to the column switch connector.
3. Turn the ignition switch to the "LOCK" (OFF) position.
4. Operate the MUT-II according to the procedure below to display "ECU COMM CHECK."
1. Select "SYSTEM SELECT."
2. Select "SWS."
3. Select "SWS MONITOR."
4. Select "ECU COMM CHECK."
5. Scan tool MB991502 should show "OK" on the "ECU COMM CHECK" menu.

Q: Are "OK" displayed on the "ETACS ECU" and "COLUMN ECU" menus?
"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 impossible."
"NG" is displayed on the "COLUMN ECU" menu : Refer to Inspection Procedure A-2 "Communication with column switch (column-ECU) is impossible."







STEP 2. Check the input signal by using "FUNCTION DIAGNOSIS" of the SWS monitor.
Check the input signals from the following switches:
- Ignition switch: OFF (key removed)
- Lighting switch: TAIL or HEAD
- Driver's door: open
- Front passenger's door: closed

Operate the MUT-II according to the procedure below to display "LGT MONI. ALRM."
1. Select "SYSTEM SELECT."
2. Select "SWS."
3. Select "SWS MONITOR."
4. Select "FUNCTION DIAGNOSIS"
5. Select "BUZZER."
6. Select "LGT MONI. ALRM."




Check that normal conditions are displayed on the items described in the table.

NOTE: The scan tool display changes when the driver's or the front passenger's door is opened. If any of the doors is open, the system can not be checked correctly.

Q: Does the scan tool display "HEADLIGHT SW", "TAILLIGHT SW", "IG SW IG1", "FRONT DOOR SW", "H/L AUTO-CUT" and "BUZZER" as normal condition?

YES: Replace the ETACS-ECU.The light reminder tone alarm function should work normally.

NO:
- The scan tool does not show the respective normal condition for item "HEADLIGHT SW." Refer to Inspection Procedure O-8 "ETACS-ECU does not receive a signal from the headlight switch."
- The scan tool does not show the respective normal condition for item "TAILLIGHT SW." Refer to Inspection Procedure O-7 "ETACS-ECU does not receive a signal from the taillight switch."
- The scan tool does not show the respective normal condition for item "IG SW (IG1)." Refer to Inspection Procedure O-2 "ETACS-ECU does not receive a signal from the ignition switch (IG1)."
- The scan tool does not show the respective normal condition for item "FRONT DOOR SW." Refer to Inspection Procedure O-6 "ETACS-ECU does not receive a signal from the driver's or the front passenger's door switch."
- The scan tool does not show the respective normal condition for item "H/L AUTO-CUT." Refer to Inspection Procedure J-9 "Headlight automatic shutdown function does not work normally."
- The scan tool does not show the respective normal condition for item "BUZZER." Replace the ETACS-ECU.The light reminder tone alarm function should work normally.