Mitsubishi Lancer Evolution IX. Manual - part 600

TROUBLESHOOTING <ACD>

MANUAL TRANSMISSION (FF)

22A-83

Code No.61 Stop lamp switch system

OPERATION

The stop lamp switch judges whether the brake 
pedal is depressed or released, and sends the infor-
mation to the 4WD-ECU.

DIAGNOSIS CODE SET CONDITIONS

Code No.61 is set when the stop lamp switch is ON 
for more than 15 minutes when the vehicle speed is 
above 15 km/h.

PROBABLE CAUSES

• Malfunction of brake pedal

• Malfunction of stop lamp switch

• Damaged harness wires and connectors

• Malfunction of the 4WD-ECU

Stop lamp switch system circuit

BATTERY

STOP LAMP SWITCH

<LH DRIVE VEHICLES> OR
<RH DRIVE VEHICLES>

<LH DRIVE VEHICLES> OR
<RH DRIVE VEHICLES>

4WD-ECU

RELAY
BOX

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

TROUBLESHOOTING <ACD>

MANUAL TRANSMISSION (FF)

22A-84

DIAGNOSIS

STEP 1. Check that the stop lamps illuminate and 
extinguish normally.
The stop lamps should illuminate when the brake 
pedal is depressed, and extinguish when released.

Q: Is the check result normal?

YES : 

Go to Step 7.

NO : 

Go to Step 2.

STEP 2. Check the brake pedal height.
Refer to GROUP 35A 

− On-vehicle Service, Brake 

Pedal Check and Adjustment 

P.35A-5

.

Q: Is the check result normal?

YES : 

Go to Step 3.

NO : 

Adjust the brake pedal height.

STEP 3. Check the stop lamp switch.
Refer to GROUP 35A 

− Brake Pedal and Stop Lamp 

Switch Continuity Check 

P.35A-15

.

Q: Is the check result normal?

YES : 

Go to Step 4.

NO : 

Replace the stop lamp switch.

STEP 4. M.U.T.-II/III data list
Item 56: Stop lamp switch (Refer to data list refer-
ence table 

P.22A-142

).

Q: Is the check result normal?

YES : 

Intermittent malfunction (Refer to GROUP 

00 

− How to Cope with Intermittent 

Malfunction 

P.00-5

).

NO : 

Go to Step 5.

STEP 5. Connector check: C-102 stop lamp 
switch connector

Check for the contact with terminals.

Q: Is the check result normal?

YES : 

Go to Step 6.

NO : 

Repair the defective connector.

STEP 6. Measure the voltage at stop lamp switch 
connector C-102.

Disconnect the stop lamp switch connector, and 
measure the voltage between terminal No.2 and 
earth at the harness side.

OK: System voltage

Q: Is the check result normal?

YES : 

Go to Step 7.

NO : 

Go to Step 12.

AC309520

Connector: C-102

Harness side

Brake pedal

AC

4

3

2

1

C-102

AC309520

Connector: C-102

Harness side

Brake pedal

AC

4

3

2

1

C-102

TROUBLESHOOTING <ACD>

MANUAL TRANSMISSION (FF)

22A-85

STEP 7. Measure the voltage at 4WD-ECU 
connector C-26.
(1) Connect the stop lamp switch connector C-102.

(2) Measure the voltage between 4WD-ECU 

connector C-26 terminal No.38 and earth.

OK:

Brake pedal depressed: System voltage
Brake pedal not depressed: 1 V or less

Q: Is the check result normal?

YES : 

Go to Step 8.

NO : 

Go to Step 10.

STEP 8. Connector check: C-26 4WD-ECU 
connector

Check for the contact with terminals.

Q: Is the check result normal?

YES : 

Go to Step 9.

NO : 

Repair the defective connector.

STEP 9. M.U.T.-II/III data list
Item 56: Stop lamp switch (Refer to data list refer-
ence table 

P.22A-142

).

Q: Is the check result normal?

YES : 

Intermittent malfunction (Refer to GROUP 

00 

− How to Cope with Intermittent 

Malfunction 

P.00-5

).

NO : 

Replace the 4WD-ECU.

AC311002

4WD-ECU

Harness side

C-26 (Y)

AC

Connector: C-26

4WD-ECU

C-26 (Y)

Rear console 
assembly

<LH drive vehicles>

<RH drive vehicles>

AC311002

4WD-ECU

Harness side

C-26 (Y)

AC

Connector: C-26

4WD-ECU

C-26 (Y)

Rear console 
assembly

<LH drive vehicles>

<RH drive vehicles>

TROUBLESHOOTING <ACD>

MANUAL TRANSMISSION (FF)

22A-86

STEP 10. Connectors check: C-26 4WD-ECU 
connector, C-105 J/C (6), C-124 intermediate 
connector.

Check for the contact with terminals.

Q: Is the check result normal?

YES : 

Go to Step 11.

NO : 

Repair the defective connector.

AC311002

4WD-ECU

Harness side

C-26 (Y)

AC

Connector: C-26

4WD-ECU

C-26 (Y)

Rear console 
assembly

<LH drive vehicles>

<RH drive vehicles>

AC311015AF

Connector: C-105 <LH drive vehicles>

C-105

AC311016AC

Connector: C-105 <RH drive vehicles>

C-105

AC311015AB

Connector: C-124 <LH drive vehicles>

C-124

AC311016AF

Connector: C-124 <RH drive vehicles>

C-124