SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-219
INSPECTION PROCEDURE F-2: Sunroof: Any of the sunroof switch positions is defective.
.
TECHNICAL DESCRIPTION (COMMENT)
The sunroof switch or the sunroof motor assembly
may be defective.
.
TROUBLESHOOTING HINTS
Refer to circuit diagrams GROUP-90
Refer to configuration diagrams GROUP-80
The sunroof switch may be defective
The sunroof motor assembly may be defective
The wiring harness or connectors may have
loose, corroded, or damaged terminals, or termi-
nals pushed back in the connector
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 sunroof 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 diagnostic tool MB991958.Refer to "How to
connect SWS monitor P.54B-13."
(2) Operate the 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."
(3) When each function of the sunroof switch is operated
(turned on), check that diagnostic tool MB991958 sounds.
Q: Does diagnostic tool MB991958 sound when the
sunroof switch is operated?
YES : Replace the sunroof motor assembly. Check that the
sunroof works at all positions normally.
NO : Refer to Inspection Procedure M-8 "ETACS-ECU
does not receive any signal from the up, open or
close/down switch P.54B-429."
SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-220
INSPECTION PROCEDURE F-3: Sunroof: Sunroof Timer Function does not Work Normally.
NOTE: This troubleshooting requires use of
diagnostic tool MB991958 and SWS monitor kit
MB991813. For details of how to use the SWS moni-
tor, refer to "How to connect SWS monitor
P.54B-13."
.
CIRCUIT OPERATION
The sunroof timer function works according to the
signals from the following switches:
Ignition switch (IG1): OFF
Front door switch: OFF
Vehicle condition
Ignition switch: LOCK position
Front door: Closed
When the driver’s door is opened and closed
while the sunroof timer function is on, the sunroof
operative duration will be changed.
.
TECHNICAL DESCRIPTION (COMMENT)
Is the sunroof timer function does not work normally,
the input circuits from the switches described in
"CIRCUIT OPERATION", the sunroof motor assem-
bly, the ETACS-ECU or the SWS communication line
may be defective.
.
TROUBLESHOOTING HINTS
Refer to circuit diagrams GROUP-90
Refer to configuration diagrams GROUP-80
The front door switch may be defective
The sunroof motor assembly may be defective
The wiring harness or connectors may have
loose, corroded, or damaged terminals, or termi-
nals pushed back in the connector
DIAGNOSIS
Required Special Tools:
MB991223: Test 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
SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-223
54B
WINDSHIELD WIPER AND WASHER
GENERAL DESCRIPTION CONCERNING THE WINDSHIELD WIPER AND WASHERM1549021500257
Refer to circuit diagrams GROUP-90
Refer to configuration diagrams GROUP-80The following ECUs affect the functions and control
of the windshield wiper and washer.
Windshield wiper and washer control function
.
Intermittent control (vehicle speed-dependent
variable type)
ETACS-ECU uses the dial position of the variable intermittent
wiper control switch and the vehicle speed signal sent by the
combination meter to calculate the interval to be sent to the
front-ECU.
NOTE: The speed-sensitive wiper can be customized on vehi-
cles equipped with a multi center display (middle grade type).
Refer to P.54B-486.
The front-ECU determines the intermittent time T1 from the
input SWS data signal, and turns ON the windshield wiper drive
signal. When the wiper is at the STOP position, the windshield
wiper auto-stop signal goes OFF, then turns OFF the wind-
shield wiper drive signal. After the intermittent time T1 seconds
from when the windshield wiper drive signal turned ON, the
windshield wiper drive signal is turned ON again and the above
operation is repeated.
NOTE: If the intermittent time T1 is within 2 seconds, the wiper
is operated consecutively at LOW-speed by the front-ECU.
.
FUNCTION CONTROL ECU
Windshield wiper and washer
control functionIntermittent control (Vehicle
speed-dependent variable type)ETACS-ECU, front-ECU, column
switch
Mist wiper control ETACS-ECU, column switch
Low speed wiper and high speed
wiper controlETACS-ECU, column switch
Washer control ETACS-ECU, column switch
SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-226
INSPECTION PROCEDURE G-1: Windshield Wiper and Washer: The windshield wiper 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 windshield wiper and washer switch sends a
signal through the column-ECU (incorporated in
the column switch) to the front-ECU. If the col-
umn-ECU sends a windshield wiper and washer
switch "ON" signal to the front-ECU, the
front-ECU turns on the relay (incorporated in the
front-ECU), thus causing the windshield wiper
and washer motor to be turned on.
If the SWS communication line is defective, the
front-ECU operates windshield wiper motor by
using the other communication lines (wiper
backup circuit) instead of that line. In this case,
the windshield wiper works at low speed regard-
less of the windshield wiper and washer switch
positions ("LO" or "HIGH").
.
TECHNICAL DESCRIPTION (COMMENT)
If the windshield wiper does not work at all, the wind-
shield wiper motor, column switch (windshield wiper
and washer switch) or the front-ECU may be defec-
tive.
.
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 wiper motor may be defective
The column switch may be defective
The front-ECU may be defective
SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-234
INSPECTION PROCEDURE G-2: Windshield Wiper and Washer: The windshield wipers do not work
when the windshield wiper switch is at "INT" or "MIST" position or the windshield washer switch is at
"ON" position. However, the wipers work at low speed when the windshield wiper switch is at "LO" or
"HI."
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."
.
TECHNICAL DESCRIPTION (COMMENT)
This system may be at fail-safe mode as the SWS
communication line is defective.
If the system cannot receive any signal from the col-
umn switch (windshield wiper and washer switch)
due to a open circuit in the SWS communication line
or other reasons, the system will enter the fail-safe
mode when the ignition switch is at the "ACC" posi-
tion.
.
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 column switch may be defective
The front-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
SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-236
INSPECTION PROCEDURE G-3: Windshield Wiper and Washer: All of the windshield wiper switch
positions are defective.
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."
.
TECHNICAL DESCRIPTION (COMMENT)
If either of the windshield wiper switch positions is
defective, the windshield wiper motor, column switch
(windshield wiper and washer switch) or the
front-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 wiper motor may be defective
The front-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
SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-241
TECHNICAL DESCRIPTION (COMMENT)
If the windshield wipers do not stop at predetermined
park position, the windshield wiper motor or the
front-ECU may be defective.
.
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 windshield wiper motor may be defective
The front-ECU may be defective
DIAGNOSIS
Required Special Tool:
MB991223: Harness Set
STEP1. Check windshield wiper motor connector A-03 for
loose, corroded or damaged terminals, or terminals
pushed back in the connector.
Q: Is windshield wiper motor connector A-03 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. Verify that the windshield wiper works
normally.
SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-246
INSPECTION PROCEDURE G-5: Windshield Wiper and Washer: The windshield intermittent wiper
interval cannot be adjusted by using the variable intermittent wiper control switch.
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."
.
TECHNICAL DESCRIPTION (COMMENT)
If the windshield intermittent wiper interval is not
changed by operating the windshield intermittent
wiper interval adjusting knob or according to the
vehicle speed, the column switch, the ETACS-ECU
or the front-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
The front-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