MPI – Troubleshooting13-20
INSPECTION PROCEDURE FOR TROUBLE SYMPTOMS
INSPECTION PROCEDURE 1
Communication with MUT-II is impossible.
(Communication with all systems is impossible.)
Probable cause
The cause is probably a defect in the power supply system (including earth) for the
diagnosis line.Malfunction of the diagnosis connector
Malfunction of the harness wire
Measure at the diagnostic connector
B-22.
Voltage between 16 and earth
OK:System voltageNGCheck the following connectors:
Repair
OK
Check trouble symptom.NGCheck the harness wire between the
power supply and diagnostic connector,
and repair if necessary.OK
Measure at the diagnostic connector
B-22.
Continuity between 4 and earth
Continuity between 5 and earth
OK:ContinuityNGCheck the earth wire, and repair if nec-
essary.
OK
Replace the MUT-II.
INSPECTION PROCEDURE 2
MUT-II communication with engine-ECU is impossible.
Probable cause
One of the following causes may be suspected.
No power supply to engine-ECU.
Defective earth circuit of engine-ECU.
Defective engine-ECU.
Improper communication line between engine-ECU and MUT-IIMalfunction of engine-ECU power supply circuit
Malfunction of engine-ECU
Open circuit between immobilizer-ECU and diagnosis
connector
OK
Check the engine-ECU power supply and earth circuit.
(Refer to P.13-53, INSPECTION PROCEDURE 45.)
NG
Check the harness wire between engine-ECU and diagnosis con-
nector.NG
Repair
OK
Check trouble symptom.
Check the following connectors:
B-22, B-65, B-32, B-61NG
Repair
54-1
CHASSIS
ELECTRICAL
CONTENTS
GENERAL 3. . . . . . . . . . . . . . . . . . . . . . . . . .
BATTERY 3. . . . . . . . . . . . . . . . . . . . . . . . . . .
SERVICE SPECIFICATION 3. . . . . . . . . . . . . . .
ON-VEHICLE SERVICE 3. . . . . . . . . . . . . . . . . .
IGNITION SWITCH
SYSTEM> 6. . . . . . . . . . . . . . . . . . . . . . . . . . .
SPECIAL TOOL 6. . . . . . . . . . . . . . . . . . . . . . . . .
TROUBLESHOOTING 6. . . . . . . . . . . . . . . . . . . .
IGNITION SWITCH 11. . . . . . . . . . . . . . . . . . . . . .
IGNITION SWITCH AND IMMOBILIZER
SYSTEM
SPECIAL TOOL 13. . . . . . . . . . . . . . . . . . . . . . .
TROUBLESHOOTING 13. . . . . . . . . . . . . . . . . .
IGNITION SWITCH AND IMMOBILIZER
SYSTEM 19. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
COMBINATION METERS 22. . . . . . . . . . . .
SERVICE SPECIFICATIONS 22. . . . . . . . . . . .
SEALANT 23. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SPECIAL TOOLS 23. . . . . . . . . . . . . . . . . . . . . .
TROUBLESHOOTING 24. . . . . . . . . . . . . . . . . .
CONTINUED ON NEXT PAGE
WARNINGS REGARDING SERVICING OF SUPPLEMENTAL RESTRAINT SYSTEM (SRS) EQUIPPED VEHICLES
WARNING!
(1) The service personnel must thoroughly review this manual, and especially its GROUP 52B – Supplemental Restraint
System (SRS) before beginning any service or maintenance of any component of the SRS or any SRS-related
component.
(2) When removing or installing the components indicated in the table of contents by an astarisk (*), use utmost care so
as not to apply any strong shock to SRS components.
NOTE
The SRS includes the following components: SRS-ECU, SRS warning lamp, air bag module, clock spring and interconnecting
wiring. Other SRS-related components (that may have to be removed/installed in connection with SRS service or maintenance) are
indicated in the table of contents by an asterisk (*).
CHASSIS ELECTRICAL – Ignition SwitchCHASSIS ELECTRICAL – Ignition Switch54-6
IGNITION SWITCH
SPECIAL TOOL
ToolNumberNameUse
MB991502MUT-II sub
assemblyETACS-ECU input signal checking
TROUBLESHOOTING
DIAGNOSIS FUNCTION
INPUT SIGNAL INSPECTION POINTS
Refer to Group 00 – How to Use Troubleshooting / Inspection
Service Points.
INSPECTION CHART FOR TROUBLE SYMPTOMS
Trouble symptomsInspection
procedureReference page
Communication with
MUTIIis impossible
Key hole illumination lamp remains illuminated.154-7
MUT-II is impossible.
Even if driver’s side door is opened, key hole
illumination lamp does not illuminate.254-7
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 10 seconds.)354-8
Key reminder warning
buzzer systemWhile 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.)354-8
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.)454-9
The key reminder warning buzzer does not sound
ever if the driver’s side door is opened while the key
is still inserted. (However, the ignition key should be
in the OFF position.)554-10
NOTE
If every input signal can not be checked with the MUT-II, a diagnosis circuit system failure is probably
the cause.
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.
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.
CHASSIS ELECTRICAL – Ignition Switch and Immobilizer System54-15
Code No. 21 Communication system between MUT-II and
engine-ECUProbable cause
After the ignition switch is turned to the ON position, the confirmation code is not
received from the engine-ECU within the allowable time, or an abnormal code is received.Malfunction of harness or connector
Malfunction of the engine-ECU
Malfunction of the immobilizer-ECU
Is diagnosis code No. 54 being gener-
ated by the engine-ECU?NOCheck the engine-ECU power source
and the earth circuit.
(Refer to GROUP 13A – Troubleshoot-
ing.)
YES
Check the following connectors.
B-100, B-65, B-61NG
Repair
OK
Check trouble symptoms.NGCheck the harness wire between
engine-ECU and immobilizer-ECU.NG
Repair
OK
Check trouble symptoms.
NG
Replace the immobilizer-ECU.
Check trouble symptoms.NGReplace the engine-ECU.
Code No. 31 EEPROM abnormality inside immobilizer-
ECUProbable cause
No data has been written to the EEPROM inside the immobilizer-ECU.Malfunction of the immobilizer-ECU
Check trouble symptoms.NGReplace the immobilizer-ECU.
CHASSIS ELECTRICAL – Ignition Switch and Immobilizer System54-16
INSPECTION CHART FOR TROUBLE SYMPTOMS
Trouble symptomInspection procedure No.Reference page
Communication with MUT-II is impossible.154-16
ID code cannot be registered using the MUT-II.254-17
Engine does not start (Cranking but no initial combustion).354-17
Malfunction of the immobilizer-ECU power source and earth circuit454-18
INSPECTION PROCEDURE FOR TROUBLE SYMPTOMS
Inspection Procedure 1
Communication with MUT-II is impossible.
Probable cause
The cause is probably that a malfunction of the diagnosis line or the immobilizer-ECU
is not functioning.Malfunction of the diagnosis line
Malfunction of harness or connector
Malfunction of the immobilizer-ECU
Can the MUT-II communicate with the
engine-ECU?NOCheck the following connectors.
B-100, B-22NG
Repair
YES
Check the immobilizer-ECU connector
B-100.
(Short-circuited harness wire between
terminal No. 13 and No. 14)NG
Repair
OK
Check trouble symptoms.
NG
Check the harness wire between immo-
bilizer-ECU and diagnosis connector.NG
Repair
OK
Check the immobilizer-ECU power sup-
ply and earth circuit. (Refer to INSPEC-
TION PROCEDURE 4.)
OK
Check trouble symptoms.NGReplace the immobilizer-ECU.
OK
CHASSIS ELECTRICAL – Ignition Switch and Immobilizer SystemCHASSIS ELECTRICAL – Ignition Switch and Immobilizer System54-17
Inspection Procedure 2
ID code cannot be registered using the MUT-II.
Probable cause
The cause is probably that there is no ID code registered in the immobilizer-ECU,
or there is a malfunction of the immobilizer-ECU.Malfunction of the transponder
Malfunction of the ignition key ring antenna
Malfunction of harness or connector
Malfunction of the immobilizer-ECU
No ignition key can be registered.NOReplace the ignition key that cannot be
registered.Re-register the ID code.
(Refer to P.54-21.)
YES
Is a diagnosis code output?NOTo INSPECTION CHART FOR DIAG-
NOSIS CODE (Refer to P.54-13.)
YES
Check the immobilizer-ECU power
source and earth circuit. (Refer to
INSPECTION PROCEDURE 4.)OKCheck trouble symptoms.NGReplace the immobilizer-ECU.
Inspection Procedure 3
Engine does not start (cranking but no initial combustion).
Probable cause
If the fuel injectors are not operating, there might be a problem with the MPI system
in addition to a malfunction of the immobilizer system.
It is normal for this to occur if an attempt is made to start the engine using a key
that has not been properly registered.Malfunction of the MPI system
Malfunction of the immobilizer-ECU
Is a diagnosis code output from the
immobilizer-ECU?NOTo INSPECTION CHART FOR DIAG-
NOSIS CODE (Refer to P.54-13.)
YES
Is a diagnosis code output from the
engine-ECU?NORefer to GROUP 13A – Troubleshoot-
ing.
YES
To inspection procedure for when there
is no initial combustion. (Refer to
GROUP 13A – Troubleshooting.)
OK
Check trouble symptoms.
NG
Check the immobilizer-ECU power sup-
ply and earth circuit (Refer to INSPEC-
TION PROCEDURE 4.)OKCheck trouble symptoms.NGReplace the immobilizer-ECU.