SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-107
DIAGNOSIS
Required Special Tools:
MB991223: Harness Set
MB991958: diagnostic 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: Test Probe Harness
STEP 1. Check the adjustment function.
Q: Has the door-ajar warning tone alarm function been
enabled by the adjustment function?
YES : Go to Step 2.
NO : Enable the door-ajar warning tone alarm.
STEP 2. Using diagnostic tool MB991958, diagnose the
CAN bus line.
To prevent damage to diagnostic tool MB991958, always
turn the ignition switch to the "LOCK" (OFF) position
before connecting or disconnecting diagnostic tool
MB991958.
(1) Connect diagnostic tool MB991958. Refer to "How to
connect SWS monitor P.54B-13."
(2) Turn the ignition switch to the "ON" position.
(3) Diagnose the CAN bus line.
(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the CAN bus line found to be normal?
YES : Go to Step 3.
NO : Repair the CAN bus line (Refer to GROUP 54C,
Diagnosis P.54C-13).
SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-110
STEP 5. Check the input signal by using "FUNCTION
DIAG." menu of the SWS monitor.
Check the input signals from the following switches:
Ignition switch: ON
Driver’s door: Open
Vehicle speed: 8 km/h (5 mph) or more
(1) Operate diagnostic tool MB991958 according to the
procedure below to display "OTHER ALARM"
a. Select "Interactive Diagnosis."
b. Select "System Select."
c. Select "SWS."
d. Select "SWS MONITOR."
e. Select "Function Diag."
f. Select "BUZZER."
g. Select "OTHER ALARM"
(2) Check that normal conditions are displayed for the items
described in the table below.
NOTE: The diagnostic tool MB991958 display changes
when the driver's or the front passenger's door is opened. If
any of the doors are open, the system cannot be checked
correctly.
Q: Does diagnostic tool MB991958 display the items "IG
SW (IG1)", "FRONT DOOR SW" and "BUZZER" as
normal condition?
Normal conditions are displayed for all the items : Go to
St e p 6 .
Normal condition is not displayed for "IG SW (IG1)" :
Refer to Inspection Procedure M-2 "ETACS-ECU
does not receive any signal from the ignition switch
(IG1) P.54B-408."
Normal condition is not displayed for "FRONT DOOR
SW" : Refer to Inspection Procedure M-4 "ETACS-ECU
does not receive any signal from the front door
switches P.54B-413."
Normal condition is not displayed for "BUZZER" :
Replace the ETACS-ECU. The ignition key reminder
tone alarm function should now work normally. ITEM NO. ITEM NAME NORMAL
CONDITION
ITEM 30 IG SW (IG1) ON
ITEM 32 FRONT DOOR SW ON
ITEM 43 BUZZER ON
SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-112
INSPECTION PROCEDURE B-5: Tone Alarm: The Multi center Display does not Sound Normally When
it is Operated.
NOTE: This troubleshooting procedure requires the
use of diagnostic tool MB991958 and SWS monitor
kit MB991813. For details on how to use the SWS
monitor, refer to "How to connect SWS monitor
P.54B-13."
.
CIRCUIT OPERATION
The ETACS-ECU sounds the buzzer when it
receives buzzer signal from the multi center display
(MID).
.
TECHNICAL DESCRIPTION (COMMENT)
If this function does not work normally, connector(s),
wiring harness in the CAN bus lines, the mid-
dle-grade multi center display unit or the
ETACS-ECU 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 ETACS-ECU may be defective
Refer to circuit diagrams GROUP-90
Refer to configuration diagrams GROUP-80
DIAGNOSIS
Required Special Tools:
MB991223: Harness Set
MB991958: diagnostic 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: Test Probe Harness
STEP 1. Check the operation of the multi center display
(MID).
Q: Does the multi center display work normally?
YES : Go to Step 2.
NO : First, replace the multi center display unit.
SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-115
STEP 5. Check the input signal by using "FUNCTION
DIAG." menu of the SWS monitor.
Turn the ignition switch to the "ON" position to check the input
signals from the following switches.
(1) Operate diagnostic tool MB991958 according to the
procedure below to display "OTHER ALARM."
a. Select "Interactive Diagnosis."
b. Select "System Select."
c. Select "SWS."
d. Select "SWS MONITOR."
e. Select "Function Diag."
f. Select "BUZZER."
g. Select "OTHER ALARM."
(2) Check that normal conditions are displayed for the items
described in the table below.
NOTE: If the function switch of the multi center display is
operated, check that No.43 "BUZZER" is displayed as nor-
mal condition.
Q: Are normal conditions displayed for the "IG SW (IG1)"
and "BUZZER"?
Normal conditions are displayed for all the items :
Replace the ETACS-ECU. Verify that the multi center
display operating sound function works normally.
Normal condition is not displayed for "IG SW (IG1)" :
Refer to Inspection Procedure M-2 "ETACS-ECU
does not receive any signal from the ignition switch
(IG1) P.54B-408."
Normal condition is not displayed for "BUZZER" :
Replace the ETACS-ECU. Verify that the multi center
display operating sound function works normally. ITEM NO. ITEM NAME NORMAL
CONDITION
ITEM 30 IG SW (IG1) ON
ITEM 43 BUZZER ON
SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-116
INSPECTION PROCEDURE B-6: Tone Alarm: Turn-signal Lamp Buzzer Function does not Work
Normally.
NOTE: This troubleshooting procedure requires use
of diagnostic tool MB991958 and SWS monitor kit
MB991813. For details on how to use the SWS mon-
itor, refer to "How to connect SWS monitor
P.54B-13."
.
CIRCUIT OPERATION
The ETACS-ECU controls the turn-signal lamp
buzzer function, based on the switch signals below:
Turn-signal lamp switch: ON
Hazard switch: ON
.
TECHNICAL DESCRIPTION (COMMENT)
If the turn-signal lamp buzzer function does not work
normally, connector(s), wiring harness, the column
switch, the ETACS-ECU or the input signal circuit
may be defective.
.
TROUBLESHOOTING HINTS
Refer to circuit diagrams GROUP-90
Refer to configuration diagrams GROUP-80
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: diagnostic 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: Test Probe Harness
STEP 1. Check the adjustment function.
Q: Has the turn-signal lamp buzzer function been enabled
by the adjustment function?
YES : Go to Step 2.
NO : Enable the turn-signal lamp buzzer function.
SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-118
STEP 4. Check the input signal by using "FUNCTION
DIAG." menu of the SWS monitor.
Check the input signals from the following switches:
Ignition switch: ON
Driver’s door: Open
All door: Closed
(1) Operate diagnostic tool MB991958 according to the
procedure below to display "OTHER ALARM"
a. Select "Interactive Diagnosis."
b. Select "System Select."
c. Select "SWS."
d. Select "SWS MONITOR."
e. Select "Function Diag."
f. Select "BUZZER."
g. Select "OTHER ALARM"
(2) Check that normal conditions are displayed for the items
described in the table below.
NOTE: The diagnostic tool MB991958 display changes
when the driver's or the front passenger's door is opened. If
any of the doors is open, the system cannot be checked
correctly.
Q: Does diagnostic tool MB991958 display the items "IG
SW (IG1)" and "BUZZER" as normal condition?
Normal conditions are displayed for all the items :
Replace the ETACS-ECU. Check that the turn-signal
lamp buzzer function works normally.
Normal condition is not displayed for "IG SW (IG1)" :
Refer to Inspection Procedure M-2 "ETACS-ECU
does not receive any signal from the ignition switch
(IG1) P.54B-408."
Normal condition is not displayed for "BUZZER" :
Replace the ETACS-ECU. Check that the turn-signal
lamp buzzer function works normally.
CENTRAL DOOR LOCKING SYSTEM
GENERAL DESCRIPTION CONCERNING CENTRAL DOOR LOCKING SYSTEMM1549021100271
The following ECUs affect the functions and control
of the central door locking system.ITEM NO. ITEM NAME NORMAL
CONDITION
ITEM 30 IG SW (IG1) ON
ITEM 43 BUZZER ON
FUNCTIONCONTROL ECU
Central door locking system ETACS-ECU
Forgotten key prevention function ETACS-ECU
INPUT SIGNAL PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-408
INSPECTION PROCEDURE M-2: ETACS-ECU does not receive any signal from the ignition switch
(IG1).
.
CIRCUIT OPERATION
The ETACS-ECU operates the following equipment
or functions according to signal from the ignition
switch (IG1):
Light reminder tone alarm function
Seat belt tone alarm function
Door ajar warning buzzer
Turn-signal lamp buzzer
Multi center display operation tone
Power window timer function
Sunroof timer function
Headlamp automatic shutdown function
Turn-signal lamp
Dome lamp dimming function
Ignition key hole illumination lamp
If the power supply circuit from the battery to the
ETACS-ECU is open, this circuit is used as
backup circuit.
If the signal is not normal, the equipment or functions
described in "CIRCUIT OPERATION" do not work
normally.
The ETACS-ECU receives information on the ignition
switch condition (IG1) from the combination meter
via CAN communication. If the ignition switch (IG1)
input signal is incorrect, refer to the Diagnostic Trou-
ble Code Chart P.54B-25.
.
TROUBLESHOOTING HINTS
Refer to circuit diagrams GROUP-90
Refer to configuration diagrams GROUP-80
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 Tool:
MB991223: Harness Set
STEP 1. Check ETACS-ECU connector C-219 for loose,
corroded or damaged terminals, or terminals pushed back
in the connector.
Q: Is ETACS-ECU connector C-219 in good condition?
YES : Go to Step 2.
NO : Repair or replace the damaged component(s). Refer
to GROUP 00E, Harness Connector Inspection
P.00E-2. If the functions described in "CIRCUIT
OPERATION" work normally, the input signal from the
ignition switch (IG1) should be normal.
INPUT SIGNAL PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-414
CIRCUIT OPERATION
The ETACS-ECU operates the following functions or
systems according to signal from the front door
switches:
Light reminder tone alarm function
Door ajar warning buzzer
Forgotten key reminder
Power window timer function
Sunroof timer function
Keyless entry system
Timed locking mechanism
Headlamp automatic shutdown function
Dome lamp
Interior lamp automatic-shutdown function
Ignition key hole illumination lamp
Door-ajar indicator lamp
.
TECHNICAL DESCRIPTION (COMMENT)
If the signal is not normal, the functions or systems
described in "CIRCUIT OPERATION" do not work
normally. If the signal is not normal, the front door
switches or the ETACS-ECU may be defective.
.
TROUBLESHOOTING HINTS
Refer to circuit diagrams GROUP-90
Refer to configuration diagrams GROUP-80
The front door switches may be defective
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