IGNITION SWITCH
CHASSIS ELECTRICAL54A-9
TROUBLESHOOTING
IGNITION KEY REMINDER BUZZER AND
DOOR LOCK PREVENTION FUNCTION
TROUBLESHOOTING
M1543000701002
The ignition key reminder buzzers are controlled by
the Smart Wiring System (SWS). For
troubleshooting, refer to respective Groups below.
•Not using SWS monitor: GROUP 54B, SWS
Diagnosis P.54B-38.
•Using SWS monitor: GROUP 54C, SWS
Diagnosis P.54C-22.
IMMOBILIZER SYSTEM
TROUBLESHOOTING
DIAGNOSIS CODE CHARTM1543007100417
CAUTION
During diagnosis, a diagnosis code associated
with other system may be set when the ignition
switch is turned on with connector(s)
disconnected. On completion, confirm all
systems for diagnosis code code(s). If diagnosis
code code(s) are set, erase them all.
Use the following chart to develop proper diagnostic
strategy. MB991223
A: MB991219
B: MB991220
C: MB991221
D: MB991222Harness set
A: Test harness
B: LED harness
C: LED harness
adapter
D: ProbeMaking voltage and
resistance measurements
during troubleshooting
A: Connect pin contact
pressure inspection
B: Power circuit inspection
C: Power circuit inspection
D: Commercial tester
connection Tool Number Name Use
MB991223
A
B
C
D
AC
Diagnosis code No. Diagnosis item Reference page
11 Transponder communication system or radio interference
of encrypted codeP.54A-10.
12 Encrypted codes are not the same or are not registered
P.54A-11.
IGNITION SWITCH
CHASSIS ELECTRICAL54A-10
DIAGNOSTIC TROUBLE CODE
PROCEDURES
Code No.11: Transponder Communication System or Radio Interference of Encrypted Code
DIAGNOSIS CODE SET CONDITION
•Diagnosis code No.11 may be set if other ignition
keys are in the vicinity of the vehicle as it is being
started.
•The transponder’s encrypted code is not sent to
the immobilizer-ECU immediately after the
ignition switch is turned to "ON" position.NOTE: Diagnosis code No.11 is always set together
with MPI system diagnosis code No.P0513.TROUBLESHOOTING HINTS
•Radio interference of the encrypted code.
•Malfunction of the transponder.
•Malfunction of the immobilizer-ECU.
HIGH-FREQUENCY
CIRCUIT IMMOBILIZER-ECU
IGNITION KEY
IGNITION KEY
RING ANTENNA
Ignition Key Ring and Immobilizer-ECU Circuit
IGNITION SWITCH
CHASSIS ELECTRICAL54A-11
DIAGNOSIS PROCEDURE
STEP 1. Check for presence of other key near the
key in the ignition.
Q: Is there any other key near the key in the ignition?
YES :
Move the other key well away from key
being used. Retest the system.
NO : Go to Step 2.
STEP 2. Check that the engine start using the
spare ignition key which encrypted code has
been registered.
Q: Does the engine start using the spare ignition key
for which the encrypted code has been registered?
YES :
Replace the ignition key that does not work.
Then register the password (secret code)
and encrypted code P.54A-20. Retest the
system.
NO : Go to Step 3.
STEP 3. Check whether the diagnosis code is
reset.
Q: Which diagnosis code is set, code No.11 or 12 the
encrypted code has been registered?
Code No.12 is set :
Refer toP.54A-11.
Code No.11 is set : Go to Step 4.
STEP 4. Connector check: Immobilizer-ECU
connector C-202-1.
Q: Are immobilizer-ECU connector C-202-1 in good
condition?
YES :
Replace immobilizer-ECU and Then
register the password (secret cod) and
encrypted code P.54A-20. Retest the
system.
NO : Repair or replace the damage
component(s).
Code No.12: Encrypted Codes are Not identical or not Registered
DIAGNOSIS CODE SET CONDITION
The encrypted code sent by the transponder is not
the same encrypted code which is registered in the
immobilizer-ECU.
NOTE: Diagnosis code No.12 is always set together
with MPI system diagnosis code No.P0513.
TROUBLESHOOTING HINTS
•The encrypted code in the ignition key has not
been properly registered.•Malfunction of immobilizer-ECU.
DIAGNOSIS PROCEDURE
Was the encrypted code registered?
YES :
Replace the immobilizer-ECU and then
re-register the encrypted code (Refer to
P.54A-20).
NO : Register the encrypted code (Refer to
P.54A-20).
SYMPTOM CHARTM1543007201075
AC303806
Connector: C-202-1
Harness side
AF
Symptom Inspection
procedure No.Reference page
Communication with MUT-II/III is impossible. 1
P.54A-12
The ignition key cannot be registered. 2
P.54A-18
Engine does not start (cranking but no initial combustion). 3
P.54A-18
IGNITION SWITCH
CHASSIS ELECTRICAL54A-14
STEP 4. Check the harness wires between
immobilizer-ECU connector C-202-1 (terminal 1)
and engine control relay connector B-16X
(terminal 4).
NOTE:
Prior to the wiring harness inspection, check
intermediate connector C-13 ,
C-137 , joint connector C-12
, C-134 and
key reminder switch connector C-202, and repair if
necessary.
Q: Are the harness wires between immobilizer-ECU
connector C-202-1 (terminal 1) and engine control
relay connector B-16X (terminal 4) in good
condition?
YES :
There is no action to be taken.
NO : Replace damaged component(s). Confirm
that MUT-II/III communicates normally.
AC303806
Connector: C-202-1
Harness side
AF
AC303796
Connector: B-16X
Harness side
AF
AC303801
Connector: C-12, C-13
C-12
C-13
C-12
C-13
AC
AC303819
Connector: C-134, C-137
C-134
C-137
C-134
C-137
AC
AC303806
Connector: C-202
Harness side
AG
IGNITION SWITCH
CHASSIS ELECTRICAL54A-15
STEP 5. Resistance measurement at
immobilizer-ECU connector C-202-1.
(1) Disconnect immobilizer-ECU connector C-202-1.
(2) Measure the resistance between terminal 4 and
earth.
OK: 2 ohms or less
Q: Is the check result normal?
YES :
Go to Step 8.
NO : Go to Step 6.
STEP 6. Connector check: immobilizer-ECU
connector C-202-1
Q: Is immobilizer-ECU connector C-202-1 in good
condition?
YES :
Go to Step 7.
NO : Repair or replace the damaged
component(s). Confirm that MUT-II/III
communicates normally.
STEP 7. Check the harness wire between
immobilizer-ECU connector C-202-1 (terminal 4)
and earth.
NOTE:
Prior to the wiring harness inspection, check joint
connector C-104 , C-07
drive vehicles>, key reminder switch connector
C-202, and repair if necessary.
AC303806
Connector: C-202-1
Harness side
AF
AC304851AB
Connector 202-1
(Harness side)
AC303806
Connector: C-202-1
Harness side
AF
AC303806
Connector: C-202-1
Harness side
AF
AC303814
Connector: C-07
C-07(GR)
Harness side
AL
AC303804AO
Harness connector: C-104
C-104(GR)
Harness side
AC303806
Connector: C-202
Harness side
AG
