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SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-201
STEP 21. Check the wiring harness between horn relay
connector A-06X (terminal 4) and horn (HIGH) connector
A-37 (terminal 1).
Q: Is the wiring harness between horn relay connector
A-06X (terminal 4) and horn (HIGH) connector A-37
(terminal 1) in good condition?
YES : Replace the ETACS-ECU. Verify that the horn sounds
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. Verify that
the horn sounds normally.
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SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-202
INSPECTION PROCEDURE E-3: Keyless Entry System: Encrypted code cannot be registered.
.
CIRCUIT OPERATION
The ETACS-ECU operates the encrypted code regis-
ter mode according to the following signals:
Key reminder switch
Hazard warning lamp switch
.
TECHNICAL DESCRIPTION (COMMENT)
If the encrypted code register mode cannot be set,
the input circuits from the switches described in
"CIRCUIT OPERATION" or the ETACS-ECU may be
defective.
If the encrypted code register mode can be set but
the transmitter cannot be registered, the transmitter
or the ETACS-ECU may be defective.
.
TROUBLESHOOTING HINTS
Refer to circuit diagrams GROUP-90
Refer to configuration diagrams GROUP-80
The key reminder switch may be defective
The hazard warning lamp switch may be defec-
tive
The transmitter may be defective
The ETACS-ECU may be defective
The wiring harness or connectors may have
loose, corroded, or damaged terminals, or termi-
nals pushed back in the connector
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
STEP 1. Verify trouble symptom.
Q: Can the encrypted code register mode be set?
YES : Go to Step 3.
NO : Go to Step 2.
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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.
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SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-204
STEP 3. Check the transmitter.
Q: When the transmitter's battery is replaced, can the
encrypted code be registered?
YES : No action is necessary and testing is complete.
NO : Replace the transmitter. If the encrypted code cannot
be registered using the new transmitter, replace the
ETACS-ECU. Verify that the encrypted code can be
registered in the transmitter.
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SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-205
INSPECTION PROCEDURE E-4: Keyless Entry System: The trunk is not opened when the keyless
entry transmitter "TRUNK" button is operated.
.
CIRCUIT OPERATION
A receiver is incorporated in the ETACS-ECU. This
receiver receives a lock or unlock signal from the
transmitter.
.
TROUBLESHOOTING HINTS
Refer to circuit diagrams GROUP-90
Refer to configuration diagrams GROUP-80
The RKE transmitter may be defective
The ETACS-ECU may be defective
The wiring harness or connectors may have
loose, corroded, or damaged terminals, or termi-
nals pushed back in the connector
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
STEP 1. Check that the doors can be locked and unlocked
by using the keyless entry transmitter.
Q: Can the doors be locked and unlocked normally when
the keyless entry transmitter is operated?
YES : Go to Step 2.
NO : Refer to Inspection Procedure E-1 "Keyless entry
system does not operate P.54B-191."
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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."
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SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-207
STEP 3. Check trunk lid latch assembly connector F-05
and ETACS-ECU connector C-217 for loose, corroded or
damaged terminals, or terminals pushed back in the
connector.
Q: Is trunk lid latch assembly connector F-05 and
ETACS-ECU connector C-217 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. Check that the headlamps illuminate
normally.
STEP 4. Check the trunk lid latch assembly.
Remove the trunk lid latch assembly. Refer to GROUP 42,
Trunk lid, Trunk lid latch inspection P.42-65.
Q: Does the windshield washer motor operate normally?
YES : Go to Step 5.
NO : Replace the trunk lid latch assembly. Verify that the
windshield washer works normally.
LEVER POSITION TESTER
CONNECTIONSPECIFIED
CONDITION
ON (Latch open) 2
Ground Less than 2 ohms
OFF (Latch shut) 2
Ground Open circuit
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SYMPTOM PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-208
STEP 5. Check the wiring harness between trunk lid latch
assembly connector F-05 (terminal 1) and ETACS-ECU
connector C-217.
NOTE: Also check intermediate connector C-28 for loose, cor-
roded, or damaged terminals, or terminals pushed back in the
connector. If intermediate connector C-28 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 lid latch assembly
connector F-05 (terminal 1) and ETACS-ECU connector
C-217 in good condition?
YES : Replace the ETACS-ECU. All the doors can be locked
or unlocked by means of the transmitter.
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. The system
should communicate with the sunroof-ECU normally.