Inspection Procedure B-2
Tone Alarm: Light reminder tone alarm function does network normally.Light Reminder Tone Alarm Function:
NOTE: This troubleshooting procedure requires the use of scan tool MB991958 and SWS monitor kit MB991813. For details on how to use the SWS monitor, refer to "How to use SWS monitor." How To Use SWS Monitor
CIRCUIT OPERATION
The ETACS-ECU operates this function in accordance with the input signals below.
- Ignition switch (IG1)
- Driver's door switch
- Taillight switch
- Headlight switch
If this function does not work normally, these input signal circuit(s) or the ETACS-ECU may be defective.
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
- The front door switches may be defective
- The column switch (turn-signal light and lighting switch) may be defective
- The ETACS-ECU may be defective
- The wiring harness or connectors may have loose, corroded, or damaged terminals, or terminals pushed back in the connector
DIAGNOSIS
Required Special Tools:
- MB991223: Harness Set
- MB991958: Scan Tool (MUT-III Sub Assembly)
- MB991824: Vehicle Communication Interface (V.C.I.)
- MB991827: MUT-III USB Cable
- MB991910: MUT-III Main Harness A
- MB991813: SWS monitor kit
- MB991806: SWS Monitor Cartridge
- MB991812: SWS Monitor Harness (For Column-ECU)
- MB991822: Probe Harness
- MB991854: SWS Monitor Harness (For 13-pin)
STEP 1. Use scan tool MB991958 to select "ECU COMM CHK" on the SWS monitor display.
Check the following ECUs:
- ETACS-ECU
- Column-ECU
CAUTION: To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991958.
1. Connect scan tool MB991958 to the data link connector (16-pin).
2. Connect SWS monitor harness MB991854 to the data link connector (13-pin).
3. Turn the ignition switch to the "LOCK" (OFF) position.
4. Operate the scan tool MB991958 according to the procedure below to display "ECU COMM CHECK."
a. Select "SYSTEM SELECT."
b. Select "SWS."
c. Select "SWS MONITOR."
d. Select "ECU COMM CHK".
5. Scan tool MB991958 should show "OK" on the "ECU COMM CHK" menus for both the "ETACS ECU" and the "COLUMN ECU" menus.
Q: Are "OK" displayed on both the "ETACS ECU" and "COLUMN ECU" menus?
YES <"OK" are displayed for all the items>: Go to Step 2.
NO <"NG" is displayed on the "ETACS ECU" menu>: Refer to Inspection Procedure A-3 "Communication with the ETACS-ECU is not possible."
NO <"NG" is displayed on the "COLUMN ECU" menu>: Refer to Inspection Procedure A-2 "Communication with the column switch (column-ECU) is not possible."
STEP 2. Check the input signal by using "FUNCTION DIAG." menu of the SWS monitor.
Check the input signals from the switches in the following conditions:
- Turn the ignition switch to the "OFF" position, (key inserted)
- Turn the lighting switch to the "TAIL" or "HEAD" position.
- Open the driver's door. (The front switch (LH) is turned to the ON position.)
- Close the front passenger's door. (The front door switch (RH) is turned to the OFF position.)
1. Operate the scan tool MB991958 according to the procedure below to display "LGT MONI. ALRM."
a. Select "SYSTEM SELECT."
b. Select "SWS."
c. Select "SWS MONITOR."
d. Select "FUNCTION DIAG."
e. Select "BUZZER."
f. Select "LGT MONI. ALRM"
2. Check that normal conditions are displayed on the items described in the table.
Q: Are normal conditions displayed for "HEADLIGHT SW", "TAILLIGHT SW", "IG SW IG1", "FRONT DOOR SW", "H/L AUTO-CUT" and "BUZZER"?
YES
NO
NO
NO
NO
NO
NO