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-117
STEP 2. Check whether the turn-signal lamps illuminate.
When the turn-signal lamp switch or the hazard warning lamp
switch is operated, check that the turn-signal lamps flash.
Q: Are the turn-signal lamps in good condition?
YES : Go to Step 3.
NO : First, repair the turn-signal lamp(s). Refer to
Inspection Procedure I-3 "One of the turn-signal
lamps does not illuminate P.54B-316."
STEP 3. Use diagnostic tool MB991958 to select "ECU
COMM Check" on the SWS monitor display.
Check the following ECUs:
ETACS-ECU
Column-ECU
To prevent damage to diagnostic tool MB991958, always
turn the ignition switch to the "LOCK" (OFF) position
before connecting or disconnecting diagnostic tool
MB991958. Connect special tool MB991910 before con-
necting special tool MB991812. Be sure to connect special
tool MB991806 after turning on special tool MB991824.
(1) Connect the special tool. Refer to "How to connect SWS
monitor P.54B-13."
(2) Turn the ignition switch to the "ON" position.
(3) Operate diagnostic tool MB991958 according to the
procedure below to display "ECU COMM Check."
1. Select "Interactive Diagnosis."
2. Select "System Select."
3. Select "SWS."
4. Select "SWS MONITOR."
5. Select "ECU COMM Check."
(4) diagnostic tool MB991958 should show "OK" on the "ECU
COMM Check" menus for both the "ETACS ECU" and the
"COLUMN ECU" menus.
Q: Is "OK" displayed for both the "ETACS ECU" and
"COLUMN ECU" menus?
"OK" is displayed for all the items : Go to Step 4.
"NG" is displayed for the "COLUMN ECU" menu : Refer
to Inspection Procedure A-2 "Communication with the
column switch (column-ECU) is not possible
P.54B-68."
"NG" is displayed for the "ETACS ECU" menu : Refer to
Inspection Procedure A-3 "Communication with the
ETACS-ECU is not possible P.54B-74."
"NG" is displayed for all the items : Refer to Inspection
Procedure A-3 "Communication with the ETACS-ECU
is not possible P.54B-74."
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
SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-142
INSPECTION PROCEDURE C-3: Central Door Locking System: All the Doors do not Lock or Unlock
with just the Door Lock Switch Operation.
.
TECHNICAL DESCRIPTION (COMMENT)
The door lock switch (incorporated in the power win-
dow main switch and front power window sub switch)
or the ETACS-ECU 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
Check the input signal (by using the pulse check mode of
the monitor).
Check the input signals from the door lock switch (incorporated
in the power window main switch and front power window sub
switch):
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 the special tool. Refer to "How to connect SWS
monitor P.54B-13."
(2) When the driver's or the front passenger's door lock switch
is moved from "LOCK" to "UNLOCK" and vice versa, check
if diagnostic tool MB991958 sounds or not.
(3) Operate diagnostic tool MB991958 according to the
procedure below to display "Pulse check."
a. Select "Interactive Diagnosis."
b. Select "System Select."
c. Select "SWS."
d. Select "Pulse Checking."
Q: Does diagnostic tool MB991958 sound when the driver's
or the front passenger's door lock switch is moved from
"LOCK" to "UNLOCK" and vice versa?
YES : Replace the ETACS-ECU. Check that all the doors
should be locked and unlocked by the door lock
switch.
NO : Refer to Inspection Procedure N-6 "ETACS-ECU
does not receive any signal from the door lock switch
(incorporated in the power window main switch and
front power window sub switch) P.54B-460."
SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-143
INSPECTION PROCEDURE C-4: Central Door Locking System: All the Doors do not Lock or Unlock
with just the Door Lock Key Cylinder Key Operation.
.
TECHNICAL DESCRIPTION (COMMENT)
The door lock key cylinder switch or the ETACS-ECU
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
Check the input signal (by using the pulse check mode of
the monitor).
Check the input signals from the door lock key cylinder switch.
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 the special tool. Refer to "How to connect SWS
monitor P.54B-13."
(2) When the doors are locked and unlocked by using the
driver's door lock key cylinder, check that diagnostic tool
MB991958 sounds.
(3) Operate diagnostic tool MB991958 according to the
procedure below to display "Pulse check."
a. Select "Interactive Diagnosis."
b. Select "System Select."
c. Select "SWS."
d. Select "Pulse Checking."
Q: When the doors are locked and unlocked by using the
driver's door lock key cylinder, does diagnostic tool
MB991958 sound?
YES : Replace the ETACS-ECU. Check that all the doors
should be locked and unlocked by using driver door
lock key cylinder switch.
NO : Refer to Inspection Procedure N-4 "ETACS-ECU
does not receive any signal from the door lock key
cylinder switch P.54B-446."
SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-144
INSPECTION PROCEDURE C-5: Central Door Locking System: Forgotten Key Prevention 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 operates the forgotten key preven-
tion function according to the following switches:
Key reminder switch: OFF
Front door switch: ON
Front door lock actuator switch: being turned on
The ETACS-ECU operates the forgotten key preven-
tion function under the following conditions:
Ignition key: inserted into the ignition key cylinder
Front door: open
Front door lock: being locked
.
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
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
SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-146
STEP 2. Check the input signal by using "DATA LIST"
menu of the SWS monitor.
Turn the ignition switch to the "ON" position before checking
input signals from the ignition switch (IG1).
(1) Operate the diagnostic tool MB991958 according to the
procedure below to display "ETACS ECU."
a. Select "Interactive Diagnosis."
b. Select "System Select."
c. Select "SWS."
d. Select "SWS MONITOR."
e. Select "Data List."
f. Select "ETACS ECU."
(2) Check that normal conditions are displayed for the items
described in the table below.
Q: Does diagnostic tool MB991958 display "FRONT DOOR
SW" as normal condition?
YES : Go to Step 3.
NO : Refer to Inspection Procedure M-4 "ETACS-ECU
does not receive any signal from the front door
switches P.54B-413." ITEM NO. ITEM NAME NORMAL CONDITION
ITEM 32 FRONT DOOR SW ON