SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-310
INSPECTION PROCEDURE I-1: Flasher Timer: Turn-signal lamps do not flash when the turn-signal
lamp switch is turned on.
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
The turn-signal lamp switch sends a signal
through the column-ECU (incorporated in the col-
umn switch) to the ETACS-ECU. If the col-
umn-ECU sends a turn-signal lamp switch "ON"
signal to the ETACS-ECU, the ETACS-ECU turns
on the flasher timer (incorporated in the
ETACS-ECU), thus causing the turn-signal lamps
to flash.
The ETACS-ECU operates the turn-signal lamps
according to the following signals:
Ignition switch (IG1): ON
Turn-signal lamp switch: ON
The ETACS-ECU flashes the turn-signal lamps
under the following conditions:
Ignition key: "ON" position
Turn-signal lamp switch: Left or right turn-sig-
nal position
.
TECHNICAL DESCRIPTION (COMMENT)
If the turn-signal lamps do not flash normally, the
input circuits from the switches described in "CIR-
CUIT OPERATION" or the ETACS-ECU may be
defective. If the hazard warning lamps do not flash,
the power supply line to the ETACS-ECU (dedicated
to the turn-signal lamps) 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 hazard warning lamp.
Q: Do the hazard warning lamps work normally?
YES : Go to Step 7.
NO : Go to Step 2.
SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-314
STEP 8. Check the input signal by using "FUNCTION
DIAG." menu of the SWS monitor.
If the Ignition switch is turned to the "ON" position and the
turn-signal lamp switch (LH) is turned on, normal conditions
should be displayed for the items described in the table below.
(1) Operate Diagnostic Tool MB991958 according to the
procedure below to display "TURN SIG.LH."
a. Select "Interactive Diagnosis."
b. Select "System select."
c. Select "SWS."
d. Select "SWS MONITOR."
e. Select "Function Diag."
f. Select "TURN SIGNAL."
g. Select "TURN SIG.LH."
(2) Check that normal conditions are displayed for the item
described in the table below.
Q: Do the Diagnostic Tool display the item "T/S LH SW" as
normal condition?
YES : Replace the ETACS-ECU. Verify that the turn-signal
lamps illuminate normally.
NO : Refer to Inspection Procedure M-5 "ETACS-ECU
does not receive any signal from the turn-signal lamp
switch P.54B-420."
INSPECTION PROCEDURE I-2: Flasher Timer: Hazard warning lamps do not flash when the hazard
warning lamp switch is turned on.
.
CIRCUIT OPERATION
If the ETACS-ECU receives "ON" signal from the
hazard warning lamp switch, the ETACS-ECU turns
on the flasher timer (incorporated in the
ETACS-ECU), thus causing the turn-signal lamps to
flash.
.
TECHNICAL DESCRIPTION (COMMENT)
If the hazard warning lamps do not flash, the power
supply line to the ETACS-ECU (dedicated to the
turn-signal lamps) or the ETACS-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 ETACS-ECU may be defective ITEM No. ITEM NAME NORMAL CONDITION
ITEM 11 T/S LH SW ON
SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-355
54B
INTERIOR LAMP
GENERAL DESCRIPTION CONCERNING THE INTERIOR LAMPM1549021800236
Refer to circuit diagrams GROUP-90
Refer to configuration diagrams GROUP-80The following ECUs affect the functions and control
of the interior lamps.
Interior lamp control function
The ETACS-ECU controls the interior lamps by turn-
ing them on and off in the following way:
When a door is opened with the ignition switch
off, the interior lamps up to a luminance of 100
percent. When a door is closed, the interior lamps
dims at a luminance of 65 percent, and goes off
30 seconds later. However if the ignition switch is
turned ON or if a door is locked while the interior
lamps is dimming, the dome lamp will go off at
that point.
When a door is opened with the ignition switch
ON, the interior lamps up at a luminance of 100
percent. When a door is closed, the interior lamps
go off.
When the ignition key is removed with all doors
closed, the interior lamps up at a luminance of
100 percent, and goes off 30 seconds later. How-
ever if the ignition key is inserted again or if a
door is locked while the interior lamps is lighting,
the interior lamps will go off at that point.
To check keyless entry operations more easily,
the interior lamps is flashed once when the doors
are locked. When the doors are unlocked, the
interior lamps at a luminance of 100 percent, and
go off 15 seconds later.
NOTE: The dimmer function can be customised on
vehicles equipped with a multi center display (middle
grade type). Refer to P.54B-486.
NOTE: The dotted lines indicate that lighting mode
when the ignition switch is turned ON, door is locked,
or any door is opened during the timer illumination
time. FUNCTION CONTROL ECU
Interior lamp control function ETACS-ECU
Interior lamp automatic-shutoff function ETACS-ECU
Ignition key hole illumination lamp function ETACS-ECU
Door ajar indicator ETACS-ECU
Seat belt indicator ETACS-ECU
SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-359
INSPECTION PROCEDURE K-1: Interior Light: The dome lamp do not illuminate and 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
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
Driver’s door lock actuator switch: ON or OFF
Interior lamp loaded signal: ON
.
TECHNICAL DESCRIPTION (COMMENT)
If the dome lamp does not illuminate 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
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
SYMPTOM PROCEDURES
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
.
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."
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
SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-386
STEP 5. Check at ETACS-ECU connector C-218 in order to
check the ignition key hole illumination lamp circuit.
(1) Disconnect ETACS-ECU connector C-218, and measure at
the wiring harness side.
(2) The ignition key hole illumination lamp should illuminate
when terminal 63 is grounded.
Q: Does the ignition key hole illumination lamp illuminate?
YES : Replace the ETACS-ECU. Verify that the ignition key
hole illumination lamp illuminates normally.
NO : Go to Step 6.
STEP 6. Check key reminder switch connector C-310 for
loose, corroded or damaged terminals, or terminals
pushed back in the connector.
Q: Is key reminder switch connector C-310 in good
condition?
YES : Go to Step 7.
NO : Repair or replace the damaged component(s). Refer
to GROUP 00E, Harness Connector Inspection
P.00E-2. Verify that the ignition key hole illumination
lamp illuminates normally.
STEP 7. Check the ignition key hole illumination lamp
bulb.
Q: Is the ignition key hole illumination lamp bulb in good
condition?
YES : Go to Step 8.
NO : Replace the bulb. Verify that the ignition key hole
illumination lamp illuminates normally.