Page 152 of 1500

SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-152
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. 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 "ON" position.
(3) Operate the 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 2.
NO : Refer to Inspection Procedure A-3 "Communication
with the ETACS-ECU is not possible P.54B-74."
Page 153 of 1500

SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-153
STEP 2. Check the input signal by using "DATA LIST"
menu of the SWS monitor.
Turn the ignition switch to the "ON" position before checking
input signals from the ignition switch (IG1).
(1) Operate the 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 items
described in the table below.
Q: Does the diagnostic tool MB991958 display "IG SW
(IG1)" as normal condition?
YES : Go to Step 3.
NO : Refer to Inspection Procedure M-2 "ETACS-ECU
does not receive any signal from the ignition switch
(IG1) P.54B-408."
STEP 3. Check power window relay connector C-203 for
loose, corroded or damaged terminals, or terminals
pushed back in the connector.
Q: Is power window relay connector C-203 in good
condition?
YES : Go to Step 4.
NO : Repair or replace the damaged component(s). Refer
to GROUP 00E, Harness Connector Inspection
P.00E-2. The power windows function should now
work normally. ITEM NO. ITEM NAME NORMAL CONDITION
ITEM 30 IG SW (IG1) ON
Page 162 of 1500

SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-162
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. 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 "ON" position.
(3) Operate the 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 2.
NO : Refer to Inspection Procedure A-3 "Communication
with the ETACS-ECU is not possible P.54B-74."
Page 163 of 1500

SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-163
STEP 2. Check the input signal by using "DATA LIST"
menu of the SWS monitor.
Turn the ignition switch to the "ON" position before checking
input signals from the ignition switch (IG1).
(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 items
described in the table below.
Q: Does the diagnostic tool MB991958 display the items
"IG SW (IG1)", "FRONT DOOR SW" as normal
condition?
Normal condition displayed for all the items : Replace
the ETACS-ECU. Verify that the power window timer
works normally.
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
(IG1) P.54B-408."
Normal condition is not displayed for "FRONT DOOR
SW" : Refer to Inspection Procedure M-4 "ETACS-ECU
does not receive any signal from the front door
switches P.54B-413." ITEM NO. ITEM NAME NORMAL CONDITION
ITEM 30 IG SW (IG1) OFF
ITEM 32 FRONT DOOR SW
Page 190 of 1500

SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-190
KEYLESS ENTRY HAZARD ANSWERBACK AND
HORN ANSWERBACK FUNCTION
.
KEYLESS ENTRY HAZARD ANSWERBACK
FUNCTION*
1
If the keyless entry transmitter is used to send a lock signal to
the ETACS-ECU, all doors are locked and the hazard warning
lamps flash once. If an unlock signal is sent, the driver's door is
unlocked first,*
2 and if a second signal is sent, all doors are
unlocked. Each time the unlock signal is sent, the hazard warn-
ing lamps flash twice.
NOTE: *
1: The hazard answerback function can be customized
using the keyless entry transmitter (Refer to Group 42 P.42-72,
Keyless Entry System) or by using the multi center display
(middle grade type). Refer to P.54B-486.
NOTE: *
2: Vehicles with a multi center display (middle grade
type) can be customized so that a single unlock operation will
unlock all doors. Refer to P.54B-486.
.
KEYLESS ENTRY HORN ANSWERBACK
FUNCTION
If the keyless entry transmitter is used to send a lock signal to
the ETACS-ECU, the first signal locks all doors while the sec-
ond signal sounds the horn once.
NOTE: : The horn answerback function can be customized by
using the keyless entry transmitter (Refer to Group 42 P.42-72,
Keyless Entry System) or by using the multi center display
(middle grade type). Refer to P.54B-486.
TIMED LOCKING MECHANISM
.After unlocking the doors with the keyless entry transmitter, if
no doors are opened, if the ignition key is not inserted or if the
locking function is not operated, the ETACS-ECU automatically
locks the doors in 30 seconds.
NOTE: The timed locking function can be customized on vehi-
cles equipped with a multi center display (middle grade type).
Refer to P.54B-486.
Page 192 of 1500

SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-192
STEP 2. Check the input signal (by using the pulse check
mode of the monitor).
Check input signals from the transmitter.
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) 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."
(3) Push the transmitter "LOCK" or "UNLOCK" button.
(4) Check that diagnostic tool MB991958 sounds
Q: When the transmitter "LOCK" or "UNLOCK" button is
turned ON, does diagnostic tool MB991958 sound?
YES : Replace the ETACS-ECU. All the doors can be locked
or unlocked by means of the transmitter.
NO : Refer to Inspection Procedure N-8 "ETACS-ECU
does not receive any signal from the lock, unlock,
trunk or panic switch P.54B-472."
Page 203 of 1500

SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-203
STEP 2. Check the input signal (by using the pulse check
mode of the monitor).
Check the input signals from the following switches:
Key reminder switch
Hazard warning lamp 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.
(1) Connect diagnostic tool MB991958.Refer to "How to
connect SWS monitor P.54B-13."
(2) 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."
(3) Check the switches (see table below) applicable for the
input signal check are operated.
(4) Check diagnostic tool MB991958 sounds or not.
Q: When the key reminder switch and the hazard warning
lamp switch are operated, does diagnostic tool
MB991958 sound in each case?
Buzzer of diagnostic tool MB991958 sounds normally. :
Replace the ETACS-ECU. Verify that the encrypted
code can be registered in the transmitter.
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 any signal from the key reminder switch
P.54B-432."
diagnostic tool MB991958 does not sound when the
hazard warning lamp switch is turned from "OFF" to
"ON" : Refer to Inspection Procedure N-2 "ETACS-ECU
does not receive any signal from the hazard warning
lamp switch P.54B-436." ITEM NAME CHECK CONDITION
Key reminder switch Remove and reinsert the
ignition key
Hazard warning lamp switch Turn the hazard warning lamp
switch from "OFF" to "ON"
position.
Page 206 of 1500
SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-206
STEP 2. Check the input signal (by using the pulse check
mode of the monitor).
Check input signals from the transmitter.
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) 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."
(3) Push the transmitter "TRUNK" button.
(4) Check that diagnostic tool MB991958 sounds
Q: When the transmitter "TRUNK" button is turned ON,
does diagnostic tool MB991958 sound?
YES : Go to Step 3.
NO : Refer to Inspection Procedure N-8 "ETACS-ECU
does not receive any signal from the lock, unlock,
trunk or panic switch P.54B-472."