Page 345 of 558

CHASSIS ELECTRICAL – Ignition Switch54-7
INSPECTION PROCEDURE FOR TROUBLE SYMPTOMS
Inspection Procedure 1
Key hole illumination lamp remains illuminated.
Probable cause
The cause is probably a harness short or a defective ETACS-ECU or buzzer ECU.Malfunction of harness wire
Malfunction of ETACS-ECU
Malfunction of buzzer ECU
Disconnect the ignition key cylinder illumination lamp connector
B-84 and measure the continuity:
Between 4 and body earth
OK:ConductingNGCheck the harness wire between the ignition key cylinder illumination
lamp and junction block, and repair if necessary.
OK
Replace the ETACS-ECU or buzzer ECU.
Inspection Procedure 2
Even if driver’s side door is opened, key hole illumination
lamp does not illuminate.
Probable cause
The cause is probably a defective key hole illumination lamp circuit system, or a
defective driver’s side door switch input circuit system if the ignition key reminder
warning buzzer is also faulty.Malfunction of driver’s side door switch
Malfunction of bulb
Malfunction of connector
Malfunction of harness wire
Malfunction of ETACS-ECU
Malfunction of buzzer ECU
OK
Replace ETACS-ECU or buzzer ECU.
MUT-II Pulse check
Driver’s side door switch input signal
OK:The MUT-II buzzer sounds once
when the driver’s side door switch
is ON.NG
Driver’s side door switch input circuit
system inspection (Refer to Inspection
Procedure 6 on P.54-10.)
OK
Disconncet the key hole illumination
lamp connector B-84, and measure at
the harness side.
Voltage between 3 and body earth
OK:System voltageNGCheck the following connectors:
B-49, B-75, B-73NG
Repair
OK
Check trouble symptom.
NG
Check the harness wire between
ETACS-ECU or buzzer ECU and fusible
link 1, and repair if necessary.
Vehicle with buzzer ECU
Remove ETACS-ECU or buzzer ECU
from junction block, and measure at the
junction block connector B-79
Ignition key cylinder illumination
lamp connector connected
Voltage between 12 and body earth
OK:System voltage
OK
OK
NG
Check the following connectors:
B-84, B-49, B-75, B-73NG
Repair
OK
Check trouble symptom.
Check the harness wire between the
ignition key cylinder illumination lamp
and fusible link 1, and repair if neces-
sary.
NG
Page 346 of 558

CHASSIS ELECTRICAL – Ignition Switch54-8
Inspection Procedure 3
While key hole illumination lamp is illuminated, ignition
key is turned to the ON position but key hole illumination
lamp does not switch off. (However, it switch off after 15
seconds.)
Probable cause
While the key reminder warning buzzer is sounding, the
ignition key is turned to the ON position but the sound
dose not stop. (However, it stops when the driver’s side
door is closed.)
The cause is probably a malfunction of the ignition switch input circuit, ETACS-ECU
or buzzer ECU. Furthermore, if there is a malfunction of a multipurpose fuse, the
cause may also be a short circuit in a harness.Malfunction of fuse
Malfunction of connector
Malfunction of harness
Malfunction of ETACS-ECU
Malfunction of buzzer ECU
OK
Replace ETACS-ECU.
MUT-II Pulse check
Ignition switch input inspection
OK:The MUT-II buzzer sounds once
when the ignition key is turned
to the ON from OFF position.
NG
Disconnect the junction block connector
B-76 and measure at the harness side.
Voltage between the terminal No.
8 and body earth.
OK:System voltageNGCheck the following connectors:
B-76, B-79Repair
OK
Check trouble symptom.
Replace the buzzer ECU.
Replace ETACS-ECU.
Check the harness wire between the
ignition switch (IG1) and junction block
and repair if necessary.
OK
Junction block harness continuity check
NG
NOTE
The stop indicated with a dotted line
applies only to vehicles with buzzer
ECU. OK
NG
Replace NG
Page 347 of 558

CHASSIS ELECTRICAL – Ignition Switch54-9
Inspection Procedure 4
The key reminder warning buzzer dose not stop sounding
even if the key is removed. (However, it stops when the
driver’s side door is closed.)
Probable cause
The cause is probably a malfunction of the key reminder switch input circuit system,
or a malfunction of ETACS-ECU, or a malfunction of buzzer ECU.Malfunction of key reminder switch
Malfunction of connector
Malfunction of harness
Malfunction of ETACS-ECU
Malfunction of buzzer ECU
YES
Check the following connectors.
B-84, B-75NG
NG
Inspect the harness between the key
reminder switch and ETACS-ECU or
buzzer ECU, and repair if necessary.
OK
Check trouble symptom.
OK
Replace the ETACS-ECU or the buzzer
ECU.OK
NG
Key reminder switch continuity inspec-
tion (Refer to P. 54-12.)NG
Replace
MUT-II Pulse check
Ignition switch input inspection
OK:The MUT-II buzzer sounds once
when the ignition key is removed
from the key cylinder.OKReplace the ETACS-ECU.
Replace
OK
Check trouble symptom
OK
Disconnect the key reminder switch
connector and connect the terminal No.
5 to the body earth. Does the buzzer
stop sounding?NOCheck the following connectors.
B-84, B-75, B-79NG
Repair
Check the harness wire between the
key reminder switch and the body earth
and repair if necessary.
Replace the buzzer ECU.
NOTE
The stop indicated with a dotted line
applies only to vehicles with buzzer
ECU.
Page 348 of 558

CHASSIS ELECTRICAL – Ignition Switch54-10
Inspection Procedure 5
The key reminder warning buzzer dose not sound even if
the driver’s side door is opened while the key is still
inserted. (However, the ignition key should be in the OFF
position.)
Probable cause
The cause is probably a malfunction of the door switch input circuit system, if the
key hole illumination lamp is also faulty. A malfunction of the key reminder switch
input circuit system is also suspected.Malfunction of door switch
Malfunction of key reminder switch
Malfunction of connector
Malfunction of harness
Malfunction of ETACS-ECU
Malfunction of buzzer ECU
Driver’s side door switch input circuit
system inspection (Refer to Inspection
Procedure 6 on P.54-10.)
OK
MUT-II Pulse check
Key reminder switch input inspection
OK:The MUT-II buzzer sounds once
when the ignition key is removed
from the key cylinder.NGKey reminder switch continuity inspec-
tion (Refer to P.54-12.)NG
Replace
OK
Inspect the harness between the key
reminder switch and junction block.NG
Repair
OK
Replace the ETACS-ECU.OK
MUT-II Pulse check
Driver’s side door switch input signal
OK:The MUT-II buzzer sounds once
when the driver’s side door switch
is turned to the ON position.NG
OK
Junction block harness continuity checkNG
Repair
OK
Inspect the harness between the key
reminder switch and body earth.
Replace the buzzer ECU.
NOTE
The stop indicated with a dotted line
applies only to vehicles with buzzer
ECU.NG
Repair
Inspection Procedure 6
Driver’s side door switch input circuit system inspection
Door switch inspectionNG
Replace
OK
Disconnect the door switch connector
D-03 and measure at the harness side.
Voltage between the terminal No.
2 and body earth
OK:System voltageNGCheck the following connectors.
B-80, B-79NG
Repair
OK
Check trouble symptom.NGCheck the harness between the ETACS-
ECU or buzzer ECU door switch and
repair if necessary.
OK
Check trouble symptom.
NG
Replace the ETACS-ECU or the buzzer
ecu.OK
Check the following connectors.
D-03
Page 349 of 558
CHASSIS ELECTRICAL – Ignition Switch54-11
IGNITION SWITCH
REMOVAL AND INSTALLATION
123 4 5
67
8 9
10 11
12
9
ETACS-ECU or buzzer ECU removal
steps
1. Cowl side trim (R.H.)
2. Junction block
3. Buzzer control unit ETACS-ECUIgnition switch removal steps
4. Hood lock release handle
5. Driver side lower panel
6. Column cover, lower
7. Column cover, upper
8. Illumination ring or ring cover
9. Key hole illumination lamp bulb
A10. Steering lock cylinder
11. Key reminder switch
12. Ignition switch
Page 350 of 558
CHASSIS ELECTRICAL – Ignition Switch54-12
REMOVAL SERVICE POINT
ASTEERING LOCK CYLINDER REMOVAL
1. Insert the key in the steering lock cylinder and turn it
to the “ACC” position.
2. Using a cross-tip (+) screwdriver (small) or a similar tool,
push the lock pin of the steering lock cylinder inward
and then remove the steering lock cylinder.
INSPECTION
IGNITION SWITCH CONTINUITY CHECK
Disconncect the ignition switch connector without removing
the ignition switch from the vehicle. Then, check the continuity
between the following terminals.
Ignition key Terminal No.Ignition key
position
123456
LOCK
ACC
ON
START
KEY REMINDER SWITCH CONTINUITY CHECK
Disconnect the key reminder switch connector with the switch
installed on the vehicle, and then check continuity.
Ignition keyTerminal No.
12
Removed
Inserted
Cross-tip (+)
screwdriverLock pin
Page 351 of 558

CHASSIS ELECTRICAL – Ignition Switch and Immobilizer System54-13
IGNITION SWITCH AND IMMOBILIZER SYSTEM
SPECIAL TOOL
ToolNumberNameUse
MB991502MUT-II sub
assemblyImmobilizer system check
(Diagnosis display using the MUT-II)
Registration of the ID code
TROUBLESHOOTING
Caution
The ID code should always be re-registered when replacing the immobilizer-ECU.
STANDARD FLOW OF DIAGNOSIS TROUBLESHOOTING
Refer to GROUP 00 – How To Use Troubleshooting/Inspection Service Points.
DIAGNOSIS FUNCTION
DIAGNOSIS CODES CHECK
Refer to GROUP 00 – How To Use Troubleshooting/Inspection Service Points.
ERASING DIAGNOSIS CODES
Refer to GROUP 00 – How To Use Troubleshooting/Inspection Service Points.
Caution
The diagnosis codes which result from disconnecting the battery cables cannot be erased.
INSPECTION CHART FOR DIAGNOSIS CODES
Diagnosis code No.Inspection itemsReference
page
11Transponder communication system54-14
12*ID code are not the same or are not registered54-14
21Communication system between MUT-II and engine-ECU54-15
31EEPROM abnormality inside immobilizer-ECU54-15
NOTE
*: Diagnosis code No. 12 is not recorded.
Page 352 of 558

CHASSIS ELECTRICAL – Ignition Switch and Immobilizer System54-14
INSPECTION PROCEDURE FOR DIAGNOSIS CODES
Code No. 11 Transponder communication systemProbable cause
The ID code of the transponder is not sent to the immobilizer-ECU immediately
after the ignition switch is turned to the ON position.
When starting the engine, one ignition key’s ID code interferes with another ignition
key’s code.Radio interference of ID codes
Malfunction of the transponder
Malfunction of the ignition key ring antenna
Malfunction of harness or connector
Malfunction of the immobilizer-ECU
No
OK
Check the following connectors.
B-100, B-101NG
Repair
OK
Check trouble symptoms.NGCheck the harness wire between immo-
bilizer-ECU and key ring antenna.NG
Repair
OK
Replace the immobilizer-ECU.
NG
Diagnosis codes checkCode No. 12 occursTo INSPECTION PROCEDURE FOR
DIAGNOSIS CODE No. 12
(Refer to P.54-14.)
Code No. 11 occurs
Check the continuity of the ignition key
ring antenna. (Refer to P.54-20.)NG
Replace
Is there another ignition key near the
ignition key that is inserted in the ignition
switch?Ye sRemove the extra ignition key.
Check trouble symptoms.
Does the engine start using the spare
ignition key which has had the ID code
registered?OKReplace the ignition key that does not
work.Re-register the ID code.
(Refer to P.54-21.) NG
Code No. 12 ID code are not the same or are not registeredProbable cause
The ID code which is sent from the transponder is not the same as the ID code
which is registered in the immobilizer-ECU.The ID code in the ignition key being used has not
been properly registered.
Malfunction of the immobilizer-ECU
Re-register the ID code.
(Refer to P.54-21.)Check trouble symptoms.NGReplace the immobilizer-ECU.