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SIMPLIFIED WIRING SYSTEM (SWS)54B-364
STEP 4. 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 5.
NO : Repair or replace the damaged component(s). Refer
to GROUP 00E, Harness Connector Inspection
P.00E-2. Verify that the dome lamp illuminates
normally.
STEP 5. Check the wiring harness between map lamp
assembly connector D-02 (terminal 1)
or overhead console assembly connector D-03 (terminal 1)
and ETACS-ECU connector C-219 (terminal
6).
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SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-365
NOTE: Also check junction block connector C-205 for loose,
corroded, or damaged terminals, or terminals pushed back in
the connector. If junction block connector C-205 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 map lamp assembly
connector D-02 (terminal 1) or
overhead console assembly connector D-03 (terminal 1)
and ETACS-ECU connector C-219
(terminal 6) in good condition?
YES : Replace the ETACS-ECU. Verify that the dome lamp
illuminates normally.
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. Verify that
the dome lamp illuminates normally.
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SIMPLIFIED WIRING SYSTEM (SWS)54B-366
INSPECTION PROCEDURE K-2: Interior Light: The front dome lamp, rear dome lamp or trunk lamp do
not illuminate or go out normally.
.
CIRCUIT OPERATION
The ETACS-ECU operates the dome lamp according
to the following signals:
Ignition switch (IG1): ON or OFF
Key reminder switch: ON or OFF
Door switches: ON or OFF
Trunk lid latch assembly: ON or OFF
Driver’s door lock actuator switch: LOCK or
UNLOCK
.
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SIMPLIFIED WIRING SYSTEM (SWS)54B-367
TECHNICAL DESCRIPTION (COMMENT)
Is the dome lamp does not flash normally, a
burned-out dome lamp bulb, the input circuits from
the switches described in "CIRCUIT OPERATION",
the power supply line to the switches or the
ETACS-ECU may be defective.
.
TROUBLESHOOTING HINTS
Refer to circuit diagrams GROUP-90
Refer to configuration diagrams GROUP-80
The front dome lamp bulb may be defective
The rear dome lamp bulb may be defective
The trunk lamp bulb 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
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SIMPLIFIED WIRING SYSTEM (SWS)54B-368
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 which of the front dome lamp, rear dome
lamp or trunk lamp do not illuminate normally.
Q: Which of the front dome lamp, rear dome lamp or trunk
lamp fail to illuminate normally?
Front dome lamp and rear dome lamp : Go to Step 2.
Front dome lamp : Go to Step 4.
Rear dome lamp : Go to Step 9.
Tru n k l am p : Go to Step 14.
STEP 2. Check map lamp assembly connector D-02
, overhead console assembly connector
D-03 and ETACS-ECU connector C-219 for
loose, corroded or damaged terminals, or terminals
pushed back in the connector.
Q: Is map lamp assembly connector D-02
sunroof>, overhead console assembly connector D-03
and ETACS-ECU connector C-219 in
good condition?
YES : Go to Step 3.
NO : Repair or replace the damaged component(s). Refer
to GROUP 00E, Harness Connector Inspection
P.00E-2. Check that the front dome lamp and rear
dome lamp illuminates normally.
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SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-369
STEP 3. Check the wiring harness between map lamp
assembly connector D-02 (terminals 1 and 2)
sunroof> or overhead console assembly connector D-03
(terminals 1 and 2) and ETACS-ECU
connector C-219 (terminals 6 and 5).
Q: Is the wiring harness between map lamp assembly
connector D-02 (terminals 1 and 2) or
overhead console assembly connector D-03 (terminals
1 and 2) and ETACS-ECU connector
C-219 (terminals 6 and 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. Check that
the front dome lamp and rear dome lamp illuminates
normally.
STEP 4. Check map lamp assembly connector D-02
or overhead console assembly
connector D-03 for loose, corroded or
damaged terminals, or terminals pushed back in the
connector.
Q: Is map lamp assembly connector D-02
sunroof> or overhead console assembly connector
D-03 in good condition?
YES : Go to Step 5.
NO : Repair or replace the damaged component(s). Refer
to GROUP 00E, Harness Connector Inspection
P.00E-2. Check that the front dome lamp illuminates
normally.
STEP 5. Check the front dome lamp bulb.
Q: Is the front dome lamp bulb in good condition?
YES : Go to Step 6.
NO : Replace the front dome lamp bulb. Check that the
front dome lamp illuminates normally.
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SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-371
STEP 8. Check the wiring harness between map lamp
assembly connector D-02 (terminals 1 and 2)
sunroof> or overhead console assembly connector D-03
(terminals 1 and 2) and ETACS-ECU
connector C-219 (terminals 6 and 5).
Q: Is the wiring harness between map lamp assembly
connector D-02 (terminals 1 and 2) or
overhead console assembly connector D-03 (terminals
1 and 2) and ETACS-ECU connector
C-219 (terminals 6 and 5) in good condition?
YES : Replace the map lamp assembly
or overhead console assembly . Check
that the front dome lamp illuminates normally.
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. Check that
the front dome lamp illuminates normally.
STEP 9. Check rear dome lamp connector D-07 for loose,
corroded or damaged terminals, or terminals pushed back
in the connector.
Q: Is rear dome lamp connector D-07 in good condition?
YES : Go to Step 10.
NO : Repair or replace the damaged component(s). Refer
to GROUP 00E, Harness Connector Inspection
P.00E-2. Check that the rear dome lamp illuminates
normally.
STEP 10. Check the rear dome lamp bulb.
Q: Is the rear dome lamp bulb in good condition?
YES : Go to Step 11.
NO : Replace the rear dome lamp bulb. Check that the rear
dome lamp illuminates normally.
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SIMPLIFIED WIRING SYSTEM (SWS)54B-373
STEP 13. Check the wiring harness between rear dome
lamp connector D-07 (terminals 1 and 2) and ETACS-ECU
connector C-219 (terminals 6 and 5).
Q: Is the wiring harness between rear dome lamp
connector D-07 (terminals 1 and 2) and ETACS-ECU
connector C-219 (terminals 6 and 5) in good condition?
YES : Replace the rear dome lamp. Check that the rear
dome lamp illuminates normally.
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. Check that
the rear dome lamp illuminates normally.
STEP 14. Check the input signal (by using the pulse check
mode of the monitor).
Check the input signals from the trunk lid latch assembly.
Check whether diagnostic tool MB991958 sounds or not
when the trunk is opened.
(1) Operate diagnostic tool MB991958 according to the
procedure below to display "Pulse checking."
a. Select "Interactive Diagnosis."
b. Select "System Select."
c. Select "SWS."
d. Select "Pulse Checking."
Q: Does diagnostic tool MB991958 sound when the trunk is
opened and closed?
YES : Go to Step 15.
NO : Refer to Inspection Procedure N-7 "ETACS-ECU
does not receive any signal from the trunk lid latch
assembly P.54B-469."