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SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-374
STEP 15. Check trunk lamp connector D-10, ETACS-ECU
connectors C-218 and C-219 for loose, corroded or
damaged terminals, or terminals pushed back in the
connector.
Q: Is trunk lamp connector D-10, ETACS-ECU connectors
C-218 and C-219 in good condition?
YES : Go to Step 16.
NO : Repair or replace the damaged component(s). Refer
to GROUP 00E, Harness Connector Inspection
P.00E-2. Check that the trunk lamp illuminates
normally.
STEP 16. Check the trunk lamp bulb.
Q: Is the trunk lamp bulb in good condition?
YES : Go to Step 17.
NO : Replace the trunk lamp bulb. Check that the trunk
lamp illuminates normally.
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SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-375
STEP 17. Check 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).
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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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SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-378
STEP 3. 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 4.
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-379
STEP 4. Check the input signal by using "DATA LIST"
menu of the SWS monitor.
Check the input signals from the following switches:
Ignition switch: OFF
Driver’s or front passenger’s door: open
(1) Operate 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 item
described in the table below.
Q: Does the diagnostic tool MB991958 display "IG SW
(IG1)" as normal condition?
YES : Go to Step 5.
NO : Refer to Inspection Procedure M-2 "ETACS-ECU
does not receive any signal from the ignition switch
(IG1) P.54B-408." ITEM NO. ITEM NAME NORMAL CONDITION
ITEM 30 IG SW (IG1) OFF
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SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-380
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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SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-381
INSPECTION PROCEDURE K-4: Interior Light: The ignition key hole illumination lamp does not
illuminate or go out 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."
.
CIRCUIT OPERATION
When the driver's door is opened with the ignition
switch at "ACC" position, the ETACS-ECU illumi-
nates the ignition key hole illumination lamp.
The ignition key hole illumination lamp goes out
in 30 seconds after the driver's door is closed.
The ignition key hole illumination lamp remains
illuminated for 30 seconds after the ignition key is
pulled out.
The ETACS-ECU operates the ignition key hole
illumination lamp according to the input signals
from the following switches:
Ignition switch (IG1): OFF
Key reminder switch: OFF
Interior lamp loaded signal: ON
Vehicle condition:
Ignition switch: "LOCK" (OFF) or "ACC" posi-
tion
Ignition key: Removed from the ignition key
cylinder
Driver’s door: Opened or closed
.
TECHNICAL DESCRIPTION (COMMENT)
If the ignition key hole illumination lamp does not illu-
minate, the input circuits from the switches described
in "CIRCUIT OPERATION", the key reminder switch
(ignition key hole illumination lamp bulb) 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