Mitsubishi Lancer (4A9 engine). Manual - part 139

HAZARD WARNING LAMP SWITCH

CHASSIS ELECTRICAL

54A-218

TROUBLESHOOTING

STANDARD FLOW OF DIAGNOSTIC 
TROUBLESHOOTING

M1541501400141

Refer to GROUP 00 

− Contents of troubleshooting .

DIAGNOSIS FUNCTION

M1541500600090

HOW TO READ DIAGNOSIS CODE

Refer to GROUP 00 

− Diagnosis function .

HOW TO ERASE DIAGNOSIS CODE

Refer to GROUP 00 

− Diagnosis function .

DIAGNOSIS CODE CHART

M1541500200081

CAUTION

On troubleshooting, if the ignition switch is turned ON while disconnecting connector(s), diagnosis 
code(s) associated with other system may be set. On completion, confirm all systems for diagnosis 
code(s). If diagnosis code(s) are set, erase them all.

DIAGNOSIS CODE PROCEDURES

Code No.B16A6 Hazard warning lamp blown fuse

DIAGNOSTIC FUNCTION
When the hazard warning lamp fuse is blown, the 
ETACS-ECU sets the diagnosis code No. B16A6.

JUDGEMENT CRITERIA
With the diagnosis code not set, when the blown fuse 
of hazard warning lamp is detected three times con-
secutively, the ETACS-ECU sets the diagnosis code 
No. B16A3.

PROBABLE CAUSES

• Damaged harness wires and connectors

• Malfunction of the ETACS-ECU

DIAGNOSIS PROCEDURE

STEP 1. Fuse check
Check if the turn-signal lamp fuse is normal.

Q: Is the check result normal?

YES : 

Go to Step 2.

NO : 

Replace the turn-signal lamp fuse.

STEP 2. Check whether the diagnosis code is 
reset.
(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 ETACS-ECU.

NO : 

The diagnosis is complete.

MB992006

Extra fine probe

Continuity check and voltage 
measurement at harness wire or 
connector

Tool

Number

Name

Use

MB992006

Diagnosis code No.

Diagnostic item

Reference page

B16A6

Hazard warning lamp blown fuse

HAZARD WARNING LAMP SWITCH

CHASSIS ELECTRICAL

54A-219

TROUBLE SYMPTOM CHART

M1541500700268

SYMPTOM PROCEDURES

Inspection Procedure 1: The hazard warning lamps do not illuminate.

CAUTION

Before replacing the ECU, ensure that the power 
supply circuit, the earth circuit and the communi-
cation circuit are normal.
COMMENTS ON TROUBLE SYMPTOM
If the hazard warning lamps do not illuminate, the 
hazard warning lamp switch input circuit in centre 
panel unit or the ETACS-ECU may have a problem.

PROBABLE CAUSES

• Malfunction of centre panel unit

• Malfunction of the ETACS-ECU

• Damaged harness wires and connectors

DIAGNOSIS PROCEDURE

STEP 1. Check that the turn-signal lamps 
operate.
Check that the turn-signal lamps illuminate normally.

Q: Is the check result normal?

YES : 

Go to Step 2.

NO : 

Diagnose the headlamps. Refer to 
Inspection Procedure 10 "The turn-signal 
lamps do not illuminate" .

STEP 2. M.U.T.-III data list
Using the ETACS-ECU service data, check the haz-
ard warning lamp signal.

• Turn ON the hazard lamp switch.

OK: Normal condition is displayed.

Q: Is the check result normal?

YES : 

Go to Step 3.

NO : 

Troubleshoot the ETACS-ECU. Refer to 
Inspection Procedure 10 "The hazard 
warning lamp switch signal is not received" .

STEP 3. Retest the system
Check that the hazard warning lamps illuminate nor-
mally.

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 : 

Replace the ETACS-ECU.

Inspection Procedure 2: The ESS (Emergency Stop signal System) function does not work normally.

CAUTION

Whenever the ECU is replaced, ensure that the 
power supply circuit, the earth circuit and the 
communication circuit are normal.
COMMENTS ON TROUBLE SYMPTOM
If the ESS (Emergency Stop signal System) function 
does not work normally, ETACS-ECU, ABS-ECU or 
ASC-ECU may be defective. Also, the ESS does not 

work when the hazard warning lamps illuminate.

PROBABLE CAUSES

• Malfunction of the ETACS-ECU

• Malfunction of the ABS-ECU

• Malfunction of the ASC-ECU

Trouble symptom

Inspection 
Procedure No.

Reference page

The hazard warning lamps do not illuminate.

1

The ESS (Emergency Stop signal System) function does not work 
normally.

2

Item No.

Item name

Normal 
condition

Item 265

Hazard switch

ON

HORN

CHASSIS ELECTRICAL

54A-220

DIAGNOSIS PROCEDURE

STEP 1. Check the hazard warning lamps.
Check that the hazard warning lamps illuminate 
when the hazard warning lamp switch is turned ON.

Q: Is the check result normal?

YES : 

Go to Step 2.

NO : 

Refer to Inspection Procedure 1 "The 
hazard warning lamps do not illuminate" .

STEP 2. M.U.T.-III other system diagnosis code
Check if diagnosis code is set to the ABS-ECU or 
ASC-ECU.

Q: Is the diagnosis code set to the any of the above?

Set to the ABS-ECU. : 

Troubleshoot the ABS. 

Refer to GROUP 35B 

− Troubleshooting .

Set to the ASC-ECU. : 

Troubleshoot the ASC. 

Refer to GROUP 35C 

− Troubleshooting .

The diagnosis code is not set. : 

Go to Step 3.

STEP 3. M.U.T.-III other system actuator test

ABS-ECU or ASC-ECU

• Item 10: ESS test mode (Refer to  <ABS> or  

<ASC>).

OK: The ESS function operates.

Q: Is the check result normal?

YES : 

Go to Step 4.

NO : 

Replace the ABS-ECU or ASC-ECU.

STEP 4. Retest the system
Check that the ESS function works normally.

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 : 

Go to Step 1.

REMOVAL AND INSTALLATION

M1541501000198

Refer to GROUP 52A 

− Instrument Centre Panel .

INSPECTION

HAZARD WARNING LAMP SWITCH 
CHECK

M1541501100247

Using the M.U.T.-III, check the data list of ETACS. It 
is judged normal if the display turns ON when the 
hazard warning lamp switch is pressed, or OFF when 
not pressed for the item No. 265: Hazard switch.

HORN

REMOVAL AND INSTALLATION

M1542100201119

AC801676

1

2

18 ± 7 N·m

18 ± 7 N·m

AB

HORN

CHASSIS ELECTRICAL

54A-221

INSTALLATION SERVICE POINT

>>A<< HORN (LOW)/HORN (HIGH) INSTALLA-
TION

Use the earth bolts as the mounting bolts for horn 
(LOW) and horn (HIGH). The earth bolts have "E" 
mark on the bolt heads.

INSPECTION

HORN RELAY CHECK

M1542100400693

Removal Steps 

•

Front bumper and radiator grille 
assembly (Refer to GROUP 51 

− 

Front Bumper Assembly and 
Radiator Grille ).

>>

A

<<

1.

Horn (HIGH)

>>

A

<<

2.

Horn (LOW)

AC805322

Battery voltage

Terminal 
number

Normal 
condition

At no energisation

3 

− 4

No 
continuity

With current supply 
[terminal 1 (+), terminal 2 
(

−)]

Continuity 
exists (2 
ohms or 
less)

ACB01899AB

Horn relay