1997 MITSUBISHI TRITON ignition

SRS ± SRS Service Precautions52B-4
Harness
connector
(No. of termi-
nals, colour)SDU terminal No.Destination of harnessCorrective action
2 pins, red1, 2Body wiring harness
Clock springReplace clock spring
±3, 4±±
±5, 6±±
14 pins, red7, 8±±
9Body wiring harness
Diagnosis connectorCorrect or replace each
wiring harness10Body wiring harness
Front wiring harness

Ignition switch (ST)
wiring harness
11Body wiring harness
Junction block (fuse
No.11)
12Body wiring harness
Junction block (fuse
No.10)
13Body wiring harness
Combination meter (SRS
warning lamp)
14±±
15Body wiring harness
Front wiring harness

Front impact sensor (+) (R.H.)Sensor cable* installation
procedures (Refer to
P 52B 39 )16Body wiring harness
Front wiring harness

Front impact sensor (+) (L.H.)P.52B-39.)
17Body wiring harness
Front wiring harness

Front impact sensor (±) (L.H.)
18Body wiring harness
Front wiring harness

Front impact sensor (±) (R.H.)
19, 20Body wiring harness
EarthCorrect or replace each
wiring harness
NOTE
The sensor cable marked with * is available as service part.
7. SRS components should not be subjected to heat over 93
C, so remove the SRS diagnosis unit,
air bag module, clock spring and front impact sensors before drying or baking the vehicle after painting.
8. Whenever you finish servicing the SRS, check warning lamp operation to make sure that the system
functions properly. (Refer to P.52B-16.)
9. Make certain that the ignition switch is OFF when the MUT-II is connected or disconnected.
10. If you have any questions about the SRS, please contact your local distributor.
NOTE
SERIOUS INJURY CAN RESULT FROM UNINTENDED AIR BAG DEPLOYMENT, SO USE ONLY
THE PROCEDURES AND EQUIPMENT SPECIFIED IN THIS MANUAL.

SRS ± Troubleshooting52B-14
Code No.43 SRS warning lamp drive circuit system
(Lamp does not switch off.)Probable cause
This diagnosis code is output when a short to earth occurs in the harness between
the lamp and the SDU while SDU is monitoring the SRS warning lamp and the lamp
is ON.
Malfunction of wiring harnesses or connectors

Malfunction of SDU

Malfunction of combination meter
SRS warning lamp inspection

Ignition switch: ON

Does lamp switch off when SDU connector C-27 is
disconnected?NoCheck the following
connectos:
C-06, C-27NG
Repair
Ye s
Replace the SDU.
OK
Check trouble symptoms.
NG
Check the harness wire
between the SDU and
combination meter, and
repair if necessary.
Code No.44 SRS warning lamp drive circuit systemProbable cause
This diagnosis code is output when a short occurs in the lamp drive circuit or a
malfunction of the output transistor inside the SDU is detected while the SDU is
monitoring the SRS warning lamp drive circuit.
Malfunction of wiring harnesses or connectors

Malfunction of SDU
Check the SRS warning lamp drive circuit system.
(Refer to P.52B-13.)OKReplace the SDU.
Code No.45 SDU non-volatile memory (EEPROM) and A/D
converter systemProbable cause
This diagnosis code is output if there is a malfunction in the SDU non-volatile memory
(EEPROM) and A/D converter.
Malfunction of SDU
Replace the SDU.
INSPECTION CHART FOR TROUBLE SYMPTOMS52400340126
Get an understanding of the trouble symptoms and check according to the inspection procedure chart.
Trouble symptomInspection procedure No.Reference page
Communication with
MUT-II is not possible.Communication with all systems is not
possible.152B-15
Communication is not possible with
SRS only.252B-15
When the ignition key is turned to ªONº (engine stopped), the
SRS warning lamp does not illuminate.Refer to diagnosis code No.43.52B-13
After the ignition switch is turned to ON, the SRS warning lamp
is still on after approximately 7 seconds have passed.Refer to diagnosis code No.43.52B-14

SRS ± Post-collision Diagnosis52B-19
POST-COLLISION DIAGNOSIS52400110154
To inspect and service the SRS after a collision (whether
or not the air bag has deployed), perform the following steps.
SRS DIAGNOSIS UNIT MEMORY CHECK
1. Connect the MUT-II to the diagnosis connector (16-pin).
Caution
Turn off the ignition switch before connecting or
disconnecting the MUT-II.
2. Read (and write down) all displayed diagnosis codes.
(Refer to P. 52B-6.)
NOTE
If the battery power supply has been disconnected or
disrupted by the collision, the MUT-II cannot communicate
with the SRS diagnosis unit. Inspect and, if necessary,
repair the body wiring harness before proceeding further.
3. Read the data list (fault duration and how many times
memories are erased) using the MUT-II.
Data list
No.Service Data ItemApplicability
91How long a problem has lastedMaximum time to be stored: 9999 minutes
(approximately 7 days)
92Number indicating houw often the memory is clearedMaximum time to be stored: 250
4. Erase the diagnosis codes and after waiting 5 seconds
or more read (and write down) all displayed diagnosis
codes. (Refer to P.52B-6.)
REPAIR PROCEDURE
WHEN AIR BAG DEPLOYS IN A COLLISION.
1. Replace the following parts with new ones.

SRS diagnosis unit (SDU) (Refer to P. 52B-26.)

Air bag module (Refer to P. 52B-28.)

Front impact sensors (Refer to P. 52B-23.)

CHASSIS ELECTRICAL ± Ignition Switch and Immobilizer System54-8
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 defective power supply system (including earth) for the
diagnosis line.
Malfunction of connector

Malfunction of harness wire
Refer to GROUP 13A ± Troubleshoot-
ing.
Inspection Procedure 2
Communication with MUT-II is impossible. (Communica-
tion with the one-shot pulse input signal only is
impossible.)
Probable cause
The cause is probably a defective one-shot pulse input circuit system of the diagnosis
line.
Malfunction of connector

Malfunction of harness wire

Malfunction of ETACS-ECU
Check the harness wire between the
diagnosis connector and junction block.OKCheck the following connectors:
C-35, C-90NG
Repair
OK
Check trouble symptoms.NGReplace the ETACS-ECU.
NG
Repair
Inspection Procedure 3
Even if the driver's side door is opened, the 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.
Malfunction of driver's side door switch

Malfunction of key hole illumination lamp

Malfunction of harness or connector

Malfunction of ETACS-ECU
Driver's side door switch input circuit
system check (Refer to Inspection Pro-
cedure 5 on P.54-9.)
OK
Key hole illumination lamp check
(Refer to P.54-22.)NG
Replace
OK
Disconnect the key reminder switch
connector C-72 and measure at the har-
ness side.

Voltage between the terminal No.1
and body earth
OK:System voltageOKCheck the following connectors:
C-72, C-86, C-91NG
Repair
OK
Check trouble symptom.
NGNG
Check the following connectors:
C-72, C-79NG
Repair
OK
Check trouble symptom.
NG
Check the harness between the key re-
minder switch and junction block, and
repair if necessary.
Check the harness between the key re-
minder switch and junction block, and
repair if necessary.OKReplace the ETACS-ECU.
NG
Repair

CHASSIS ELECTRICAL ± Ignition Switch and Immobilizer System54-9
Inspection Procedure 4
Key hole illumination lamp remains illuminated.
Probable cause
The cause is probably a short harness or a defective ETACS-ECU.
Malfunction of harness

Malfunction of ETACS-ECU
When the connector C-86 of the junction block is disconnected,
does the lamp switch off?NoCheck the harness between the key reminder switch and junction
block, and repair if necessary.
Ye s
Replace the ETACS-ECU.
Inspection Procedure 5
Driver's side door switch input circuit system check
Door switch check (Refer to GROUP
42 ± Door Assembly.)NG
Replace
OK
Door switch earth checkNG
Repair
OK
Disconnect the door switch connector
D-17 and measure at the harness side.

Voltage between the terminal No.2
and body earth
OK:5 VNGCheck the following connectors:
C-87, D-17, D-21NG
Repair
OK
Replace the ETACS-ECU.
OK
Check trouble symptom.NGCheck the harness between the door
switch and junction block, and repair
if necessary.

CHASSIS ELECTRICAL ± Ignition Switch and Immobilizer System54-10
Immobilizer System
Caution
1. The ID code should always be re-registered when replacing the immobilizer-ECU. vehicles>
2. If the immobilizer-ECU has been replaced, you will need to re-register the ignition key ID codes
and to reset the code for the fuel cut valve controller to the factory setting. vehicles>
3. If the immobilizer-ECU has been replaced with a new part, the password (vehicle secret code)
which has been stored in the immobilizer-ECU for each vehicle will be replaced by the password
(secret code) specified by the customer.
STANDARD FLOW OF DIAGNOSIS TROUBLESHOOTING54300690024
Refer to GROUP 00 ± How To Use Troubleshooting/Inspection Service Points.
DIAGNOSIS FUNCTION54300700116
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

54300710027
Diagnosis code No.Inspection itemsReference
page
11Transponder communication system or radio interference of ID code54-11
12*ID code are not the same or are not registered54-11
21Communication system between MUT-II and engine-ECU54-12
31EEPROM abnormality inside immobilizer-ECU54-12
NOTE
*: Diagnosis code No. 12 is not recorded.

CHASSIS ELECTRICAL ± Ignition Switch and Immobilizer System54-11
INSPECTION PROCEDURE FOR DIAGNOSIS CODES

Code No.11 Transponder communication system or radio
interference of ID codeProbable cause

The ID code of the transponder is not sent to the immobilizer-ECU immediately
after the ignition switch is turned to ON position.

If the engine is started while several ignition keys are in the vicinity, then interference
between the different keys may occur, which will cause this code to be generated.
Radio interference of ID code

Malfunction of transponder

Malfunction of ignition key ring antenna

Malfunction of harness or connector

Malfunction of immobilizer-ECU
Are there any other ignition keys in the
vicinity of the ignition key being used
to for starting?Ye sMove other keys well away from key
being used.
NoCheck trouble symptom.
NG
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.54-23.)
NG
Diagnosis code checkCode No.12
occurs.To INSPECTION PROCEDURE FOR
DIAGNOSIS CODE No.12.
Code No.11 occurs.
Ignition key ring antenna continuity
check (Refer to P.54-22.)NG
Replace
OK
Check the following connectors:
C-36, C-71NG
Repair
OK
Check trouble symptom.NGCheck the harness between the immobi-
lizer-ECU and key ring antenna.NG
Repair
OK
Replace the immobilizer-ECU.Register the password (secret code)
and ID code. (Refer to P.54-23.)
Code No.12 ID codes are not the same or not registered.Probable 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 immobilizer-ECU
Re-register the ID code
(Refer to P.54-23.)Check trouble symptom.NGReplace the immobilizer-ECU.
Register the password (secret code)
and ID code. (Refer to P.54-23.)

CHASSIS ELECTRICAL ± Ignition Switch and Immobilizer System54-12
Code No.21 Communication system between MUT-II and
engine-ECUProbable cause
After the ignition switch turned to ON, the confirmation code is not received from
the engine-ECU within allowable time, or an abnormal code is received.
Malfunction of harness or connector

Malfunction of engine-ECU

Malfunction of immobilizer-ECU
Is diagnosis code No.54 displayed from
the engine-ECU?Ye sCheck the engine-ECU power source
and the earth circuit. (Refer to GROUP
13A ± Troubleshooting.)
No
Check the following connectors:
C-19, C-36, C-50NG
Repair
OK
Check trouble symptom.NGCheck the harness between the engine-
ECU and immobilizer-ECU.NG
Repair
OK
Check trouble symptom.
NG
Replace the immobilizer-ECU.
Register the password (secret code)
and ID code. (Refer to P.54-23.)
Check trouble symptom.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 immobilizer-ECU
Check trouble symptom.NGReplace the immobilizer-ECU.Register the password (secret code)
and ID code. (Refer to P.54-23.)