SYMPTOM PROCEDURES
TSB Revision
SIMPLIFIED WIRING SYSTEM (SWS)
54B-120
INSPECTION PROCEDURE B-4: Tone Alarm: Door ajar Warning Buzzer 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 controls the door-ajar warning tone
alarm, based on the signals from the switches and
sensors below.
• Ignition switch (IG1): ON
• One of the door switches: ON
• Vehicle speed signal: 8 km/h (5 mph) or more
.
TECHNICAL DESCRIPTION (COMMENT)
If the door-ajar warning tone alarm does not work,
connector(s), wiring harness in the CAN bus lines,
the combination meter, the ETACS-ECU or the input
signal circuit may be defective.
.
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 combination meter may be defective
• The ETACS-ECU may be defective
ETACS-
ECU
VEHICLES SPEED
SIGNAL
·
ALL DOOR
SWITCHES
· IGNITION SWITCH (IG1)
COMBINATION
METER
CPU
CAN COMMUNICATION LINE
(CAN_L LINE)
CAN COMMUNICATION LINE
(CAN_H LINE)
Door Ajar Tone Alarm Function Circuit