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SYMPTOM PROCEDURES
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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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SYMPTOM PROCEDURES
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STEP 11. Check the ground circuit to the rear dome lamp.
Measure the resistance at rear dome lamp connector D-07.
(1) Disconnect rear dome lamp connector D-07 and measure
the resistance available at the wiring harness side of the
connector.
(2) Measure the resistance value between terminal 3 and
ground.
The resistance should be 2 ohms or less.
Q: Is the measured resistance 2 ohms or less?
YES : Go to Step 13.
NO : Go to Step 12.
STEP 12. Check the wiring harness between rear dome
lamp connector D-07 and ground.
Q: Is the wiring harness between rear dome lamp
connector D-07 and ground 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.
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SYMPTOM PROCEDURES
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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."
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SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-376
NOTE: Also check intermediate connector C-28 and junction
block connector C-204 for loose, corroded, or damaged termi-
nals, or terminals pushed back in the connector. If intermediate
connector C-28 or junction block connector C-204 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 trunk lamp connector
D-10 (terminals 1 and 2) and ETACS-ECU connector
C-219 (terminal 6) or C-218 (terminal 46) in good
condition?
YES : Replace the trunk lamp. Check that the trunk 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 trunk lamp illuminates normally.
INSPECTION PROCEDURE K-3: Interior lamp: Dome lamp dimming function does not work normally.
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."
.
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SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-377
CIRCUIT OPERATION
The ETACS-ECU operates the dome lamp dimming
function according to the input signals from the fol-
lowing switches:
Ignition switch (IG1): OFF
Key reminder switch: ON
Door switches: OFF
Driver's door lock actuator switch: LOCK or
UNLOCK
.
TECHNICAL DESCRIPTION (COMMENT)
If the dome lamps do not dim normally, the input cir-
cuits from the switches described in "CIRCUIT
OPERATION" 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
MB991813: SWS Monitor Kit
MB991806: SWS Monitor Cartridge
MB991812: SWS Monitor Harness (For Column-ECU)
MB991822: Test Probe Harness
STEP 1. Check the dome lamp.
If a door is opened while the dome lamp switch is at
"door-linked" position, the dome lamp should illuminate.
Q: Does the dome lamp illuminate normally?
YES : Go to Step 2.
NO : Refer to Inspection Procedure K-1 "The dome lamp
do not illuminate and go out normally P.54B-359."
STEP 2. Check the adjustment function.
Q: Has the dome lamp delay-off time been set to other than
"0 second" by the adjustment function?
YES : Go to Step 3.
NO : Set the dome lamp delay-off time to "0 second."
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STEP 5. Check the input signal (by using the pulse check
mode of the monitor).
Check the input signals from the following switches:
Key reminder switch
Door switches
Trunk lid latch assembly
(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, or the
trunk lid is operated, does diagnostic tool MB991958
sound?
Buzzer of diagnostic tool MB991958 sounds normally. :
Replace the ETACS-ECU. Verify that the dome lamp
dimming function works normally.
Diagnostic tool MB991958 does not sound when the
ignition key is removed and reinserted : Refer to
Inspection Procedure N-1 "ETACS-ECU does not
receive a signal from the key reminder switch
P.54B-432."
Diagnostic tool MB991958 does not sound whenever a
door switch is operated : Refer to Inspection Procedure
N-3 "ETACS-ECU does not receive any signal from
any of the door switches P.54B-440."
When the trunk lid is opened and closed, diagnostic
tool MB991958 does not sound. : Refer to Inspection
Procedure N-7 "ETACS-ECU does not receive any
signal from trunk lid latch assembly P.54B-469." ITEM NAME CONDITION
key reminder switch Remove and reinsert the ignition
key
door switches Open or close one of the doors
trunk lid latch assembly Open or close the trunk lid
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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
MB991813: SWS Monitor Kit
MB991806: SWS Monitor Cartridge
MB991812: SWS Monitor Harness (For Column-ECU)
MB991822: Test Probe Harness
STEP 1. Check the interior lamps.
If the interior lamp switch is moved to the "door interlock posi-
tion", the interior lamps should illuminate when either door is
opened.
Q: Do the interior lamp illuminate normally?
All the interior lamps illuminate normally. : Go to Step 2.
None of the interior lamps illuminate normally. : Refer to
Inspection Procedure K-1 "The dome lamp do not
illuminate and go out normally P.54B-359."
Some of the interior lamps do not illuminate normally. :
Refer to Inspection Procedure K-2 "The front dome
lamp, rear dome lamp or trunk lamp do not illuminate
or go out normally P.54B-366."
STEP 2. Check the adjustment function.
Q: Has a setting other than "No auto-shutoff" been
selected for the interior lamp automatic shutdown
function by the adjustment function?
YES : Go to Step 3.
NO : Set the interior lamp automatic shutdown function to
another setting other than "No auto-shutoff".
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STEP 5. Check the input signal (by using the pulse check
mode of the monitor).
Check the following switches and input signals:
Door switches
Interior lamp loaded signal
(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 any door switch, interior lamp or the trunk lid
latch is operated, does diagnostic tool MB991958
sound?
Buzzer of diagnostic tool MB991958 sounds normally. :
Replace the ETACS-ECU. Verify that the dome lamp
illuminates normally.
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."
When one of the interior lamps is illuminated,
diagnostic tool MB991958 does not sound : Refer to
Inspection Procedure N-9 "ETACS-ECU does not
receive any interior lamp loaded signal P.54B-474." ITEM NAME CONDITION
interior lamp loaded
signalTurn on one of the interior lamps
door switch Open or close one of the doors