Mitsubishi Lancer (4A9 engine). Manual - part 243

ACA00897

AB

A-78 (B)

Connector: A-78

ACA00891

AB

Connector: C-63 <LHD>

ACA00896

AB

Connector: C-63 <RHD>

AC612708

Connector: C-201 <LHD>

AT

AC612716 AK

Connector: C-201 <RHD>

C-201

ACA00886

AG

Connectors: C-301, C-316 <LHD>
ETACS-ECU

C-301

C-316

ACA00887

AG

Connector: C-301, C-316 <RHD>
ETACS-ECU

C-316

C-301

ACA00898

Connectors: D-02, D-06, D-45

D-02

D-45 (B)

AC

D-06 (GR)

AC612730

Connector: E-14 <LHD>

AH

AC612735

Connector:E-14 <RHD>

AF

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TROUBLE JUDGEMENT
The ETACS-ECU will set diagnosis code No. U1515 
when no communication has been carried out for 
more than a certain period after the slave task 
received last valid data.

PROBABLE CAUSES

• Malfunction of the ETACS-ECU

• Malfunction of the slave ECU

• LIN bus lines shorted to power supply

• LIN bus lines shorted to earth

DIAGNOSIS PROCEDURE

STEP 1. Check the following connectors.
Check the following connectors:

• C-301 and C-316 <vehicles with sunroof> 

ETACS-ECU connectors

• C-201 Column switch connector

• E-14 Power window main switch connector

• D-06 Sunroof motor assembly connector <vehi-

cles with sunroof>

• D-02 Lighting control sensor connector <vehicles 

with auto lamp>

• D-45 Security alarm sensor connector <vehicles 

with security alarm sensor>

• A-78 Security alarm siren connector <vehicles 

with security alarm sensor>

• C-63 LIN cutoff control unit connector <vehicles 

with security alarm sensor>

Q: Are all the connectors in good condition?

YES : 

Go to Step 2.

NO : 

Repair the defective connector.

STEP 2. LIN cutoff control unit check
Check the LIN cutoff control unit. Refer to GROUP 
54A 

− Security Alarm System .

Q: Is the check result normal?

YES : 

Go to Step 3.

NO : 

Replace the LIN cutoff control unit.

STEP 3. Measure the voltage at the LIN bus lines.
Check the LIN bus lines for short to power supply.
(1) Disconnect all the ECU connectors which are 

connected to the LIN bus lines.

(2) Turn the ignition switch from "LOCK" (OFF) to 

"ON" position.

(3) Measure the voltage between C-201 column 

switch connector terminal No.3 and earth.

• The voltmeter needle does not swing.

NOTE: If the LIN bus lines are short to power 
supply, the voltmeter indicates a constant value.

(4) Measure the resistance value between E-14 

power window main switch connector terminal 
No.X and earth.

• No continuity (1 kΩ or more)

(5) Measure the voltage between D-06 sunroof 

motor assembly connector terminal No.7 and 
earth. <vehicles with sunroof>

• The voltmeter needle does not swing.

NOTE: If the LIN bus lines are short to power 
supply, the voltmeter indicates a constant value.

(6) Measure the voltage between D-02 lighting 

control sensor connector terminal No.3 and earth. 
<vehicles with auto lamp>

• The voltmeter needle does not swing.

NOTE: If the LIN bus lines are short to power 
supply, the voltmeter indicates a constant value.

(7) Measure the voltage between D-45 security 

alarm sensor connector terminal No.3 and earth. 
<vehicles with security alarm sensor>

• The voltmeter needle does not swing.

NOTE: If the LIN bus lines are short to power 
supply, the voltmeter indicates a constant value.

(8) Measure the voltage between A-78 security 

alarm siren connector terminal No.3 and earth. 
<vehicles with security alarm sensor>

• The voltmeter needle does not swing.

NOTE: If the LIN bus lines are short to power 
supply, the voltmeter indicates a constant value.

Q: Is the check result normal?

YES : 

Go to Step 4.

NO : 

Repair the wiring harness.

STEP 4. Measure the resistance at the LIN bus 
lines.
Check the LIN bus lines for short to earth.
(1) Disconnect all the ECU connectors which are 

connected to the LIN bus lines.

(2) Measure the resistance value between C-201 

column switch connector terminal No.3 and earth.

• No continuity (1 kΩ or more)

(3) Measure the resistance value between D-06 

sunroof motor assembly connector terminal No.7 
and earth. <vehicles with sunroof>

• No continuity (1 kΩ or more)

(4) Measure the resistance value between D-02 

lighting control sensor connector terminal No.3 
and earth. <vehicles with auto lamp>

• No continuity (1 kΩ or more)

(5) Measure the resistance value between D-45 

security alarm sensor connector terminal No.3 
and earth. <vehicles with security alarm sensor>

• No continuity (1 kΩ or more)

(6) Measure the resistance value between A-78 

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security alarm siren connector terminal No.3 and 
earth. <vehicles with security alarm sensor>

• No continuity (1 kΩ or more)

Q: Is the check result normal?

YES : 

Go to Step 5.

NO : 

Repair the wiring harness.

STEP 5. Check the column switch.
Disconnect C-201 column switch connector, and 
recheck whether diagnosis code No. U1515 is set.
(1) Connect all the relevant ECUs, and disconnect 

C-201 column switch connector only.

(2) Erase the diagnosis code.
(3) Turn the ignition switch from "LOCK" (OFF) to 

"ON" position.

(4) Check whether diagnosis code No. U1515 is set.

NOTE: If diagnosis code No. U1515 is not set, 
diagnosis code No. U1109 is set because the col-
umn switch is disconnected. This is normal.

(5) Turn the ignition switch to the "LOCK" (OFF) 

position.

Q: Is diagnosis code No. U1515 set?

YES : 

Reconnect the column switch connector, 

and go to Step 6.

NO : 

Replace the lighting switch.

STEP 6. Check the power window main switch.
Disconnect E-14 power window main switch connec-
tor, and recheck whether diagnosis code No. U1515 
is set.
(1) Connect all the relevant ECUs, and disconnect E-

14 power window main switch connector only.

(2) Erase the diagnosis code.
(3) Turn the ignition switch from "LOCK" (OFF) to 

"ON" position.

(4) Check whether diagnosis code No. U1515 is set.

NOTE: If diagnosis code No. U1515 is not set, 
diagnosis code No. U0215 is set because the 
power window main switch is disconnected. This 
is normal.

(5) Turn the ignition switch to the "LOCK" (OFF) 

position.

Q: Is diagnosis code No. U1515 set?

YES : 

Reconnect the power window main switch 

connector, and go to Step 7.

NO : 

Replace the power window main switch.

STEP 7. Check the sunroof motor assembly.
Disconnect D-06 sunroof motor assembly connector, 
and recheck whether diagnosis code No. U1515 is 
set.
(1) Connect all the relevant ECUs, and disconnect 

D-06 sunroof motor assembly connector only.

(2) Erase the diagnosis code.
(3) Turn the ignition switch from "LOCK" (OFF) to 

"ON" position.

(4) Check whether diagnosis code No. U1515 is set.

NOTE: If diagnosis code No. U1515 is not set, 
diagnosis code No. U0169 is set because the 
sunroof motor assembly is disconnected. This is 
normal.

(5) Turn the ignition switch to the "LOCK" (OFF) 

position.

Q: Is diagnosis code No. U1515 set?

YES : 

Reconnect the sunroof motor assembly 

connector, and go to Step 8.

NO : 

Replace the sunroof motor assembly.

STEP 8. Check the lighting control sensor.
Disconnect D-02 lighting control sensor connector, 
and recheck whether diagnosis code No. U1515 is 
set.
(1) Connect all the relevant ECUs, and disconnect 

D-02 lighting control sensor connector only.

(2) Erase the diagnosis code.
(3) Turn the ignition switch from "LOCK" (OFF) to 

"ON" position.

(4) Check whether diagnosis code No. U1515 is set.

NOTE: If diagnosis code No. U1515 is not set, 
diagnosis code No. U0231 is set because the 
sunroof motor assembly is disconnected. This is 
normal.

(5) Turn the ignition switch to the "LOCK" (OFF) 

position.

Q: Is diagnosis code No. U1515 set?

YES : 

Reconnect the lighting control sensor, and 

go to Step 9.

NO : 

Replace the lighting control sensor.

STEP 9. Check the security alarm sensor.
Disconnect D-45 security alarm sensor connector, 
and recheck whether diagnosis code No. U1515 is 
set.
(1) Connect all the relevant ECUs, and disconnect 

D-45 security alarm sensor connector only.

(2) Erase the diagnosis code.
(3) Turn the ignition switch from "LOCK" (OFF) to 

"ON" position.

(4) Check whether diagnosis code No. U1515 is set.

NOTE: If diagnosis code No. U1515 is not set, 
diagnosis code No. U1007 is set because the 
security alarm sensor is disconnected. This is 
normal.

(5) Turn the ignition switch to the "LOCK" (OFF) 

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position.

Q: Is diagnosis code No. U1515 set?

YES : 

Reconnect the security alarm sensor 

connector, and go to Step 10.

NO : 

Replace the security alarm sensor.

STEP 10. Check the security alarm siren.
Disconnect A-78 security alarm siren connector, and 
recheck whether diagnosis code No. U1515 is set.
(1) Connect all the relevant ECUs, and disconnect A-

78 security alarm siren connector only.

(2) Erase the diagnosis code.
(3) Turn the ignition switch from "LOCK" (OFF) to 

"ON" position.

(4) Check whether diagnosis code No. U1515 is set.

NOTE: If diagnosis code No. U1515 is not set, 
diagnosis code No. U1006 is set because the 
security alarm siren is disconnected. This is nor-
mal.

(5) Turn the ignition switch to the "LOCK" (OFF) 

position.

Q: Is diagnosis code No. U1515 set?

YES : 

Reconnect the security alarm siren 

connector, and go to Step 11.

NO : 

Replace the security alarm siren.

STEP 11. Recheck for diagnosis code.
Check again if the diagnosis code is set to the 
ETACS-ECU.
(1) Erase the diagnosis code.
(2) Turn the ignition switch from "LOCK" (OFF) to 

"ON" position.

(3) Check whether diagnosis code No. U1515 is set.
(4) Turn the ignition switch to the "LOCK" (OFF) 

position.

Q: Is the diagnosis code set?

YES : 

Replace the ETACS-ECU.

NO : 

The trouble can be an intermittent 
malfunction (Refer to GROUP 00 

− How to 

Cope with Intermittent Malfunction ).

Code No.U1539 Security alarm siren LIN checksum error <Vehicles with security alarm sensor>

JUDGMENT CRITERIA
The ETACS-ECU will set diagnosis code No. U1539 
when abnormal signals are received from the secu-
rity alarm siren.

PROBABLE CAUSES

• Faulty security alarm siren

DIAGNOSIS PROCEDURE

Check whether the diagnosis code is reset.
Check again if the diagnosis code is set to the 
ETACS-ECU.
(1) Erase the diagnosis code.

(2) Turn the ignition switch from "LOCK" (OFF) 

position to "ON" position.

(3) Check if diagnosis code is set.

Q: Is the diagnosis code set?

YES : 

Replace the security alarm siren.

NO : 

A poor connection, open circuit, or other 
intermittent malfunctions in the LIN bus lines 
between the security alarm siren and the 
ETACS-ECU (Refer to GROUP 00 

− How to 

Cope with Intermittent Malfunction ).

Code No.U1540 Security alarm SNSR.LIN checksum error <Vehicles with security alarm sensor>

JUDGMENT CRITERIA
The ETACS-ECU will set diagnosis code No. U1540 
when abnormal signals are received from the secu-
rity alarm sensor.

PROBABLE CAUSES

• Faulty security alarm sensor

DIAGNOSIS PROCEDURE

Check whether the diagnosis code is reset.
Check again if the diagnosis code is set to the 
ETACS-ECU.
(1) Erase the diagnosis code.
(2) Turn the ignition switch from "LOCK" (OFF) 

position to "ON" position.

(3) Check if diagnosis code is set.