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SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-272
STEP 2. Check the input signal by using "DATA LIST"
menu of the SWS monitor.
Turn the passing switch to the "ON" position before checking
input signals from the passing switch.
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) Operate Diagnostic Tool MB991958 according to the
procedure below to display "COLUMN ECU."
a. Select "Interactive Diagnosis."
b. Select "System select."
c. Select "SWS."
d. Select "SWS MONITOR."
e. Select "Data List."
f. Select "COLUMN ECU."
(3) Check that normal conditions are displayed for the items
described in the table below.
Q: Does the Diagnostic Tool MB991958 display "PASSING
SW" as normal condition?
YES : Replace the front-ECU. When the passing switch is
turned "ON", the headlamps (low-beam and
high-beam) should illuminate normally.
NO : Refer to Inspection Procedure M-5 "ETACS-ECU
does not receive any signal from the passing switch
P.54B-420." ITEM NO. ITEM NAME NORMAL CONDITION
ITEM 03 PASSING SW ON
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SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-274
Use Diagnostic Tool MB991958 to select "ECU COMM
Check" on the SWS monitor display.
Check the following ECUs:
ETACS-ECU
Column-ECU
Front-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 "System select."
b. Select "SWS."
c. Select "SWS MONITOR."
d. Select "ECU COMM Check."
(4) Diagnostic Tool MB991958 should show "OK" on the "ECU
COMM Check" menus for the "ETACS ECU", "COLUMN
ECU" and "FRONT ECU" menus.
Q: Is "OK" displayed for both the "ETACS ECU", "COLUMN
ECU" and "FRONT ECU" menus?
"OK" is displayed for all the items : Replace the
front-ECU. Verify that the headlamps and the
taillamps illuminate normally.
"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 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 "FRONT ECU" menu : Refer to
Inspection Procedure A-4 "Communication with the
front-ECU is not possible P.54B-80."
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SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-302
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 headlamps.
When the lighting switch is operated, check that the headlamps
illuminate/go off normally.
Q: Are the headlamps in good condition?
YES : Go to Step 2.
NO : First, repair the headlamps. Refer to Inspection
Procedure H-7 "One of the headlamps does not
illuminate P.54B-290."
STEP 2. Using Diagnostic Tool MB991958, diagnose the
CAN bus line.
To prevent damage to Diagnostic Tool MB991958, always
turn the ignition switch to the "LOCK" (OFF) position
before connecting or disconnecting Diagnostic Tool
MB991958.
(1) Connect Diagnostic Tool MB991958.Refer to "How to
connect SWS monitor P.54B-13."
(2) Turn the ignition switch to the "ON" position.
(3) Diagnose the CAN bus line.
(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the CAN bus line found to be normal?
YES : Go to Step 3.
NO : Repair the CAN bus line (Refer to GROUP 54C,
Diagnosis P.54C-15).
Page 303 of 1500
SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-303
STEP 3. Using Diagnostic Tool MB991958, read the
combination meter diagnostic trouble code.
Check whether a combination meter-related DTC is set.
(1) Turn the ignition switch to the "ON" position.
(2) Check whether the combination meter-related DTC is set.
(3) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the DTC set?
YES : Diagnose the combination meter. Refer to P.54A-48.
NO : Go to Step 4.
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SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-304
STEP 4. Use Diagnostic Tool MB991958 to select "ECU
COMM Check" on the SWS monitor display.
Check the ETACS-ECU.
Connect special tool MB991910 before connecting special
tool MB991812. Be sure to connect special tool MB991806
after turning on special tool MB991824.
(1) Connect the SWS monitor. 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 5.
NO : Refer to Inspection Procedure A-3 "Communication
with the ETACS-ECU is not possible P.54B-74."
STEP 5. Replace the combination meter.
(1) Replace the combination meter.
(2) Check that the high beam indicator lamp illuminates
normally.
Q: Does the high beam indicator lamp illuminate normally?
YES : No action is necessary and testing is complete.
NO : Replace the ETACS-ECU. Check that the high beam
indicator lamp illuminates normally.
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SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-305
INSPECTION PROCEDURE H-9: Headlamp and Taillamp: Headlamp automatic shutoff 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."
.
CIRCUIT OPERATION
The ETACS-ECU operates the headlamp automatic
shutdown function according to the following signals:
Ignition switch (IG1): OFF
Driver's door switch: ON
Taillamp switch: ON
Headlamp switch: ON
The ETACS-ECU operates the headlamp automatic
shutdown function under the following conditions:
Ignition key: Other than "ON" position
Driver's door: open
Taillamps or headlamps: on
.
TECHNICAL DESCRIPTION (COMMENT)
If the function does not work normally, the input cir-
cuit system from the switches, the ETACS-ECU or
the front-ECU may be defective (refer to "CIRCUIT
OPERATION").
.
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 front-ECU may be defective
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SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-307
STEP 2. Check the input signal by using "DATA LIST"
menu of the SWS monitor.
Check the input signals from the following switches:
Ignition switch: "ON" to "OFF"
Lighting switch: "TAIL" or "HEAD"
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 "H/L AUTO-CUT."
a. Select "Interactive Diagnosis."
b. Select "System select."
c. Select "SWS."
d. Select "SWS MONITOR."
e. Select "Function Diag."
f. Select "LIGHTING."
g. Select "H/L AUTO-CUT."
(4) Check that normal conditions are displayed for the items
described in the table below.
(5) When the driver's door is opened, check that normal
conditions are displayed for the items described in the table
below.
Q: Does the Diagnostic Tool MB991958 display the items
"TAILLAMP SW", "IG SW IG1", "FRONT DOOR SW" and
"H/L AUTO-CUT" as normal condition?
Normal conditions are displayed for all the items :
Replace the front-ECU. Verify that the headlamp
automatic shutdown function works normally.
Normal condition is not displayed for "TAILLAMP SW" :
Refer to Inspection Procedure M-5 "ETACS-ECU
does not receive any signal from the taillamp switch
P.54B-420."
Normal condition is not displayed for "IG SW (IG1)" :
Refer to Inspection Procedure M-2 "ETACS-ECU
does not receive any signal from the ignition switch ITEM NO. ITEM NAME NORMAL CONDITION
ITEM 01 TAILLAMP SW ON
ITEM 30 IG SW (IG1) OFF
ITEM NO. ITEM NAME NORMAL CONDITION
ITEM 32 FRONT DOOR SW ON
ITEM 35 H/L AUTO-CUT ON
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SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-309
FLASHER TIMER
GENERAL DESCRIPTION CONCERNING THE FLASHER TIMERM1549023600238
Refer to circuit diagrams GROUP-90
Refer to configuration diagrams GROUP-80The following ECUs affect the functions and control
of the flasher timer.
FLASHER TIMER FUNCTION
.
TURN-SIGNAL LAMP
The turn-signal lamp output (flashing signal) is turned ON when
the ignition switch is ON and the turn-signal lamp switch is ON
(LH or RH). If the front turn-signal lamp or rear turn-signal lamp
bulb has burned out, the flashing speed increases to indicate
that the bulb has burned out.
NOTE: If LH or RH side turn signal lamp bulbs have burned
out, the flashing speed will remain the same.
.
TURN-SIGNAL INDICATORS
At the same time that the turn-signal lamps are illuminated, the
ETACS-ECU sends a signal to illuminate the turn-signal lamp
indicator via the CAN bus line. The combination meter receives
the transmitted signal and turns the turn-signal lamp indicator
on and off.
.
HAZARD WARNING LAMP
Detects the signal where the hazard warning lamp switch input
changes from OFF to ON, and reverse the flashing state
according to this signal. The hazard warning lamps toggle on
and off whenever the hazard warning lamp switch is operated.
NOTE: The hazard warning lamp switch is a push-return type
toggle switch. FUNCTION CONTROL ECU
Turn-signal lamp ETACS-ECU, column switch
Turn-signal indicators ETACS-ECU, column switch
Hazard warning lamp ETACS-ECU