SYMPTOM PROCEDURES
TSB Revision
SIMPLIFIED WIRING SYSTEM (SWS)
54B-112
INSPECTION PROCEDURE B-2: Tone Alarm: Light Reminder Tone Alarm Function does not Work
Normally.
NOTE: This troubleshooting procedure requires the
use of scan tool MB991958 and SWS monitor kit
MB991813. For details on how to use the SWS mon-
itor, refer to "How to use SWS monitor
P.54B-15
."
.
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
• Front door switch (LH): 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 cylin-
der
• Driver’s door: open
• Taillights or headlights: ON
.
TECHNICAL DESCRIPTION (COMMENT)
If the function does not work normally, the input cir-
cuit system from the switches or the ETACS-ECU
may be defective (refer to "CIRCUIT OPERATION").
.
TROUBLESHOOTING HINTS
• Trouble in input signal system
• The wiring harness or connectors may have
loose, corroded, or damaged terminals, or termi-
nals pushed back in the connector
• The ETACS-ECU may be defective
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
Light Reminder Tone Alarm Function
ETACS-
ECU
· DRIVER'S DOOR SWITCH
· HEADLIGHT SWITCH
· IGNITION SWITCH (IG1)
· TAILLIGHT SWITCH
INPUT SIGNAL