Mitsubishi Lancer (4A9 engine). Manual - part 241

TROUBLESHOOTING

LOCAL INTERCONNECT NETWORK (LIN)

54B-15

Code No.U1007 Security alarm sensor LIN timeout <Vehicles with security alarm sensor>

CAUTION

Before replacing the ECU, ensure that the communication circuit is normal.

INTERFACE 
CIRCUIT

LIN DRIVE 
CIRCUIT

ETACS-
ECU

FUSE     

8

Wire colour code 
B : Black     LG : Light green     G : Green     L : Blue     W : White     Y : Yellow     SB : Sky blue 
BR : Brown     O : Orange     GR : Grey     R : Red     P : Pink     V : Violet     PU : Purple     SI : Silver

SECURITY ALARM 
SENSOR

Security Alarm Sensor LIN Communication Circuit

ACA00886

AE

Connectors: C-316, C-317 <LHD>
ETACS-ECU

C-317

C-316

ACA00887

AE

Connectors: C-316, C-317 <RHD>
ETACS-ECU

C-317

C-316

ACA00898

AB

Connector: D-45

D-45 (B)

TROUBLESHOOTING

LOCAL INTERCONNECT NETWORK (LIN)

54B-16

JUDGEMENT CRITERIA
The ETACS-ECU will set diagnosis code No. U1007 
when no signals are received from the security alarm 
sensor.

PROBABLE CAUSES

• Faulty security alarm sensor

• Malfunction of the LIN bus

DIAGNOSIS PROCEDURE

STEP 1. Connector check: C-316 and C-317 
ETACS-ECU connectors, D-134 security alarm 
sensor connector

Q: Is the check result normal?

YES : 

Go to Step 2.

NO : 

Repair the defective connector.

STEP 2. Resistance measurement at the D-45 
security alarm sensor connector
(1) Disconnect the connector, and measure at the 

wiring harness side.

(2) Measure the resistance between the D-45 

security alarm sensor connector terminal No. 3 
and the body earth.

OK: Continuity exists (2 

Ω or less)

Q: Is the check result normal?

YES : 

Go to Step 4.

NO : 

Go to Step 3.

STEP 3. Wiring harness check from D-45 security 
alarm sensor connector terminal No. 3 to body 
earth
Check the earth wires for open circuit.
NOTE: Prior to the wiring harness inspection, check 
intermediate connector D-44, and repair if necessary.

Q: Is the check result normal?

YES : 

The trouble can be an intermittent 

malfunction (Refer to GROUP 00 

− How to 

use Troubleshooting/inspection Service 
Points 

− How to Cope with Intermittent 

Malfunction ).

NO : 

Repair the wiring harness.

STEP 4. Voltage measurement at the D-45 
security alarm sensor connector.
(1) Disconnect the connector, and measure at the 

wiring harness side.

(2) Measure the voltage between the D-45 security 

alarm sensor connector terminal No. 1 and the 
body earth.

OK: System voltage

Q: Is the check result normal?

YES : 

Go to Step 6.

NO : 

Go to Step 5.

STEP 5. Wiring harness check between the D-45 
security alarm sensor connector terminal No. 1 
and the C-317 ETACS-ECU connector terminal 
No. 10
Check the power supply line for open circuit and 
short circuit.
NOTE: Prior to the wiring harness inspection, check 
intermediate connector D-44, and repair if necessary.

Q: Is the check result normal?

YES : 

The trouble can be an intermittent 

malfunction (Refer to GROUP 00 

− How to 

use Troubleshooting/inspection Service 
Points 

− How to Cope with Intermittent 

Malfunction ).

NO : 

Repair the wiring harness.

TROUBLESHOOTING

LOCAL INTERCONNECT NETWORK (LIN)

54B-17

STEP 6. Check the wiring harness wires between 
C-316 ETACS-ECU connector terminal No. 1 and 
D-45 security alarm sensor connector terminal 
No. 2.
Check the communication lines for open circuit.
NOTE: Prior to the wiring harness inspection, check 
intermediate connector C-130 and D-44, and repair if 
necessary.

Q: Is the check result normal?

YES : 

Go to Step 7.

NO : 

Repair the wiring harness.

STEP 7. 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 the LOCK (OFF) 

position to the ON position.

(3) Check if diagnosis code is set.

Q: Is the diagnosis code set?

YES : 

Replace the security alarm sensor.

NO : 

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

− How to 

Cope with Intermittent Malfunction ).

TROUBLESHOOTING

LOCAL INTERCONNECT NETWORK (LIN)

54B-18

Code No.U1109 Column SW LIN timeout

CAUTION

Before replacing the ECU, ensure that the communication circuit is normal.

Column Switch LIN Communication Circuit

Wire colour code 
B : Black     LG : Light green     G : Green     L : Blue     W : White     Y : Yellow     SB : Sky blue 
BR : Brown     O : Orange     GR : Grey     R : Red     P : Pink     V : Violet     PU : Purple     SI : Silver

ETACS-
ECU

INTERFACE 
CIRCUIT

LIN DRIVE 
CIRCUIT

FUSE     

8

COLUMN 
SWITCH

COLUMN-ECU

AC612708

Connector: C-201 <LHD>

AT

AC612716 AK

Connector: C-201 <RHD>

C-201