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STEP 7. Check the wiring harness between front-ECU
connector A-12X (terminal 21) and ground.
Q: Is the wiring harness between front-ECU connector
A-12X (terminal 21) and ground in good condition?
YES : No action is necessary and testing is complete.
NO : The wiring harness may be damaged or the
connector(s) may have loose, corroded or damaged
terminals, or terminals pushed back in the connector.
Repair the wiring harness as necessary. The system
should communicate with the front-ECU normally.
STEP 8. Check ETACS-ECU connector C-218 for loose,
corroded or damaged terminals, or terminals pushed back
in the connector.
Q: Is ETACS-ECU connector C-218 in good condition?
YES : Go to Step 9.
NO : Repair or replace the damaged component(s). Refer
to GROUP 00E, Harness Connector Inspection
P.00E-2. The system should communicate with the
front-ECU normally.
STEP 9. Check the wiring harness between front-ECU
connector A-12X (terminal 30) and ETACS-ECU connector
C-218 (terminal 53).
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NOTE: Also check intermediate connector C-29 for loose, cor-
roded, or damaged terminals, or terminals pushed back in the
connector. If intermediate connector C-29 is damaged, repair or
replace the connector as described in GROUP 00E, Harness
Connector Inspection P.00E-2.
Q: Is the wiring harness between front-ECU connector
A-12X (terminal 30) and ETACS-ECU connector C-218
(terminal 53) in good condition?
YES : Go to Step 10.
NO : The wiring harness may be damaged or the
connector(s) may have loose, corroded or damaged
terminals, or terminals pushed back in the connector.
Repair the wiring harness as necessary. The system
should communicate with the front-ECU normally.
STEP 10. Replace the front-ECU.
(1) Replace the front-ECU.
(2) The system should communicate with the front-ECU
normally.
Q: Can the system communicate with the front-ECU?
YES : No action is necessary and testing is complete.
NO : Replace the ETACS-ECU. The system should
communicate with the front-ECU normally.
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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
STEP 1. Check sunroof motor assembly connector D-04
for loose, corroded or damaged terminals, or terminals
pushed back in the connector.
Q: Is sunroof motor assembly connector D-04 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. The system should communicate with the
sunroof-ECU normally.
STEP 2. Check the fusible link (5) line of power supply
circuit to the sunroof motor assembly. Measure the voltage
at sunroof motor assembly connector D-04.
(1) Disconnect sunroof motor assembly connector D-04 and
measure the voltage available at the wiring harness side of
the connector.
(2) Measure the voltage between terminal 1 and ground.
The voltage should measure approximately 12 volts
(battery positive voltage).
Q: Is the measured voltage approximately 12 volts (battery
positive voltage)?
YES : Go to Step 4.
NO : Go to Step 3.
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SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-90
NOTE: Also check junction block connectors C-212, C-215 and
intermediate connector C-27 for loose, corroded, or damaged
terminals, or terminals pushed back in the connector. If junction
block connector C-212, C-215 or intermediate connector C-27
is damaged, repair or replace the damaged component(s) as
described in GROUP 00E, Harness Connector Inspection
P.00E-2.
Q: Is the wiring harness between sunroof motor assembly
connector D-04 (terminal 1) and fusible link (5) in good
condition?
YES : No action is necessary and testing is complete.
NO : The wiring harness may be damaged or the
connector(s) may have loose, corroded or damaged
terminals, or terminals pushed back in the connector.
Repair the wiring harness as necessary. The system
should communicate with the sunroof-ECU normally.
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NOTE: Also check junction block connectors C-215 and C-205
for loose, corroded, or damaged terminals, or terminals pushed
back in the connector. If junction block connector C-215 or
C-205 is damaged, repair or replace the damaged compo-
nent(s) as described in GROUP 00E, Harness Connector
Inspection P.00E-2.
Q: Is the wiring harness between sunroof motor assembly
connector D-04 (terminal 2) and the ignition switch (IG2)
in good condition?
YES : No action is necessary and testing is complete.
NO : The wiring harness may be damaged or the
connector(s) may have loose, corroded or damaged
terminals, or terminals pushed back in the connector.
Repair the wiring harness as necessary. The system
should communicate with the sunroof-ECU normally.
STEP 6. Check the ground circuit to the sunroof motor
assembly. Measure the resistance at sunroof motor
assembly connector D-04.
(1) Disconnect sunroof motor assembly connector D-04 and
measure the resistance available at the wiring harness side
of the connector.
(2) Measure the resistance value between terminal 5 and
ground.
The resistance should be 2 ohms or less.
Q: Is the measured resistance 2 ohms or less?
YES : Go to Step 8.
NO : Go to Step 7.
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STEP 7. Check the wiring harness between sunroof motor
assembly connector D-04 (terminal 5) and ground.
Q: Is the wiring harness between sunroof motor assembly
connector D-04 (terminal 5) and ground in good
condition?
YES : No action is necessary and testing is complete.
NO : The wiring harness may be damaged or the
connector(s) may have loose, corroded or damaged
terminals, or terminals pushed back in the connector.
Repair the wiring harness as necessary. The system
should communicate with the sunroof-ECU normally.
STEP 8. Check ETACS-ECU connector C-218 for loose,
corroded or damaged terminals, or terminals pushed back
in the connector.
Q: Is ETACS-ECU connector C-218 in good condition?
YES : Go to Step 9.
NO : Repair or replace the damaged component(s). Refer
to GROUP 00E, Harness Connector Inspection
P.00E-2. The system should communicate with the
sunroof-ECU normally.
STEP 9. Check the wiring harness between sunroof motor
assembly connector D-04 (terminal 10) and ETACS-ECU
connector C-218 (terminal 53).
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NOTE: Also check intermediate connector C-27 for loose, cor-
roded, or damaged terminals, or terminals pushed back in the
connector. If intermediate connector C-27 is damaged, repair or
replace the damaged component(s) as described in GROUP
00E, Harness Connector Inspection P.00E-2.
Q: Is the wiring harness between sunroof motor assembly
connector D-04 (terminal 10) and ETACS-ECU connector
C-218 (terminal 53) in good condition?
YES : Go to Step 10.
NO : The wiring harness may be damaged or the
connector(s) may have loose, corroded or damaged
terminals, or terminals pushed back in the connector.
Repair the wiring harness as necessary. The system
should communicate with the sunroof-ECU normally.
STEP 10. Replace the sunroof motor assembly.
(1) Replace the sunroof motor assembly.
(2) The system should communicate with the sunroof-ECU
normally.
Q: Can the system communicate with the sunroof-ECU?
YES : No action is necessary and testing is complete.
NO : Replace the ETACS-ECU. The system should
communicate with the sunroof-ECU normally.
TONE ALARM
GENERAL DESCRIPTION CONCERNING THE TONE ALARMM1549021000326
The tone alarm functions are as follows. These func-
tions are controlled by relevant ECUs.
FUNCTION CONTROL ECU
Light reminder tone alarm function ETACS-ECU, column switch
Seat belt tone alarm function ETACS-ECU
Door ajar warning buzzer ETACS-ECU
Center display operation tone
display >ETACS-ECU
Turn-signal lamp buzzer ETACS-ECU, column switch
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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."