Mitsubishi Lancer (4A9 engine). Manual - part 233
SECURITY ALARM
CHASSIS ELECTRICAL
54A-594
DIAGNOSIS PROCEDURE
STEP 1. M.U.T.-III diagnosis code.
Check if diagnosis code is set to the ETACS-ECU.
Q: Is the diagnosis code set?
YES :
Diagnose the ETACS-ECU. Refer to
GROUP 54A, Diagnosis .
NO :
Go to Step 2.
STEP 2. Security alarm siren operation check
(1) Set the security alarm to the "Ready to be
triggered" condition.
(2) Open the driver's door by using the ignition key.
(3) Check that the security alarm siren sounds.
Q: Is the check result normal?
YES :
The trouble can be an intermittent
malfunction (Refer to GROUP 00
− How to
Cope with Intermittent Malfunction ).
NO :
Go to Step 3.
STEP 3. Replace the security alarm siren
temporarily, and check whether the diagnosis
code is set.
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 ETACS-ECU.
NO :
Replace the security alarm siren.
Code No.B120B Security alarm sensor error
CAUTION
Before replacing the ECU or sensor, ensure that the power supply circuit, the earth circuit and the
communication circuit are normal.
DIAGNOSTIC FUNCTION
The security alarm sensor communicates with the
ETACS-ECU via the LIN bus line. If the diagnosis
code No. B120B is set, the security alarm sensor
itself may be defective.
NOTE:
.
•
Diagnosis code No.B120B may be set when the
security alarm sensor cover is improperly
installed or is removed. Check if the security
alarm sensor cover is properly installed.
•
Diagnosis code No.B120B is set when the ultra-
sonic wave transmission/reception part of the
security alarm sensor is covered. Check if the
ultrasonic wave transmission/reception part of the
security alarm sensor was covered.
TROUBLESHOOTING HINT
Malfunction of the security alarm sensor
DIAGNOSIS PROCEDURE
STEP 1. M.U.T.-III diagnosis code.
Check if diagnosis code is set to the ETACS-ECU.
Q: Is the diagnosis code set?
YES :
Diagnose the ETACS-ECU. Refer to
GROUP 54A, Diagnosis .
NO :
Go to Step 2.
STEP 2. Security alarm sensor operation check
Ultrasonic wave sensor check
1. With the windows of the vehicle opened, set the
security alarm to the "Ready to be triggered" con-
dition.
2. Put the arm from the outside to the inside of the
vehicle.
3. Check that the security alarm siren sounds.
Tilt angle sensor check
1. Set the security alarm to the "Ready to be trig-
gered" condition.
2. Raise the front wheels or rear wheels.
3. Check that the security alarm siren sounds.
Q: Is the check result normal?
YES :
The trouble can be an intermittent
malfunction (Refer to GROUP 00
− How to
Cope with Intermittent Malfunction ).
NO :
Go to Step 3.
STEP 3. M.U.T.-III diagnosis code.
Check if diagnosis code No. B120A is set to the
ETACS-ECU.
Q: Is diagnosis code No. B120A set?