Page 145 of 1500

SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-145
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. Use diagnostic tool MB991958 to select "ECU
COMM Check" on the SWS monitor display.
Check the ETACS-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 "LOCK" (OFF) position.
(3) Operate diagnostic tool MB991958 according to the
procedure below to display "ECU COMM Check."
a. Select "Interactive Diagnosis."
b. Select "System Select."
c. Select "SWS."
d. Select "SWS MONITOR."
e. Select "ECU COMM Check."
(4) diagnostic tool MB991958 should show "OK" on the "ECU
COMM Check" menu for the "ETACS ECU" menu.
Q: Is "OK" displayed for the "ETACS ECU" menu?
YES : Go to Step 2.
NO : Refer to Inspection Procedure A-3 "Communication
with the ETACS-ECU is not possible P.54B-74."
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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
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SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-147
STEP 3. Check the input signal (by using the pulse check
mode of the monitor).
Check the following switches and input signals:
Key reminder switch
Door switches
(1) 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."
(2) Check if diagnostic tool MB991958 sounds or not.
Q: When the key reminder switch, any door switch is
operated, does diagnostic tool MB991958 sound?
Buzzer of diagnostic tool MB991958 sounds normally. :
Replace the ETACS-ECU. The forgotten key
prevention function should work normally.
When the ignition key is removed and inserted,
diagnostic tool MB991958 does not sound. : Refer to
Inspection Procedure N-1 "ETACS-ECU does not
receive any signal from the key reminder switch
P.54B-432."
When one of the doors is opened and closed,
diagnostic tool MB991958 does not sound : Refer to
Inspection Procedure N-3 "ETACS-ECU does not
receive any signal from any of the door switches
P.54B-440." ITEM NAME CONDITION
key reminder switch Remove and reinsert the ignition key
Door switches Open or close one of the doors
Page 148 of 1500
SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-148
POWER WINDOWS
GENERAL DESCRIPTION CONCERNING THE POWER WINDOWSM1549021900244
The following ECUs affect the functions and control
of the power windows.Refer to circuit diagrams GROUP-90
Refer to configuration diagrams GROUP-80
FUNCTION CONTROL ECU
Power window main
switch functionRaises the driver’s power window Power window main switch
Lowers the driver’s power window Power window main switch
Lowers the driver’s power window by one-touch down
functionPower window main switch
Raises the passenger’s power window Power window main switch
Lowers the passenger’s power window Power window main switch
Power window sub
switch functionRaises the passenger’s power window Power window sub switch
Lowers the passenger’s power window Power window sub switch
Power window timer function ETACS-ECU
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SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-149
POWER WINDOW MAIN SWITCH FUNCTION
The main switch is located on the driver’s door.
Raises the driver’s power window
When the driver’s power window switch on the power window
main switch is pulled up, the system energizes its respective
power window motor, and then the driver’s window glass rises.
Lowers the driver’s power window
When the driver’s power window switch on the power window
main switch is pushed down, the system energizes its respec-
tive power window motor, and then the driver’s window glass
lowers.
Lowers the driver’s power window by one-touch down
function
When the driver’s power window switch on the power window
main switch is pushed down fully, the system energizes its
respective power window motor, and then the driver’s window
glass moves to its lowest position.
Raises the passenger’s power window
When the passenger’s power window switch on the power win-
dow main switch is pulled up, the system energizes its respec-
tive power window motor, and then the passenger’s window
glass rises.
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SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-150
Lowers the passenger’s power window
When the passenger’s power window switch on the power win-
dow main switch is pushed down, the system energizes its
respective power window motor, and then the passenger’s win-
dow glass lowers.
POWER WINDOW SUB SWITCH FUNCTION
The sub switches are located on the passenger’s doors.
Raises the passenger’s power window
When the power window sub switch is pulled up, the system
energizes its respective power window motor, and then the
passenger’s window glass rises.
Lowers the passenger’s power window
When the power window sub switch is pushed down, the sys-
tem energizes its respective power window motor, and then the
passenger’s window glass lowers.
Power window timer function
Even after the ignition is switched off, the ETACS-ECU keeps
the power window relay activated for approximately 30 sec-
onds, enabling raising and lowering of the power windows by
using the power window switches. After approximately 30 sec-
onds, the power window relay is deactivated.
During this timed operation, if the driver or passenger doors are
opened, the power window relay is deactivated from that
moment.
Page 151 of 1500
SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-151
INSPECTION PROCEDURE D-1: Power Windows: Power windows do not work at all.
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 turns on the power window relay
(installed on the junction block) to activate the power
windows when the ignition switch (IG1) is turned to
the "ON" position.
.
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 power window relay may be defective
The power window main switch may be defective
The ETACS-ECU may be defective
Page 152 of 1500

SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-152
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. Use diagnostic tool MB991958 to select "ECU
COMM Check" on the SWS monitor display.
Check the ETACS-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 the diagnostic tool MB991958 according to the
procedure below to display "ECU COMM Check."
a. Select "Interactive Diagnosis."
b. Select "System Select."
c. Select "SWS."
d. Select "SWS MONITOR."
e. Select "ECU COMM Check."
(4) diagnostic tool MB991958 should show "OK" on the "ECU
COMM Check" menu for the "ETACS ECU" menu.
Q: Is "OK" displayed for the "ETACS ECU" menu?
YES : Go to Step 2.
NO : Refer to Inspection Procedure A-3 "Communication
with the ETACS-ECU is not possible P.54B-74."