Mitsubishi Evolution X. Manual — part 783

DIAGNOSIS

TSB Revision

ACTIVE SKID CONTROL SYSTEM (ASC)

35C-139

STEP 8. Stoplight switch continuity check
(1) Remove the stoplight switch. (Refer to GROUP 35A

− Brake

Pedal

P.35A-25

.)

(2) Connect the circuit tester (

Ω range) to the stoplight switch

connector terminal Nos. 1 and 2.

(3) When continuity does not exist with the plunger pressed

from the outer case end face by the dimension shown in the
figure, and when continuity exists with the plunger released,
the switch is in good condition.

Q: Is the check result normal?

YES : Go to Step 9.
NO : Replace the stoplight switch. (Refer to GROUP 35A

−

Brake Pedal

P.35A-25

.) Then go to Step 11.

STEP 9. Brake booster check
Refer to GROUP 35A

− On-vehicle Service

P.35A-15

.

Q: Is the check result normal?

YES : Go to Step 10.
NO : Replace the brake booster. (Refer to GROUP 35A

−

Master Cylinder Assembly and Brake Booster

P.35A-27

.) Then go to Step 11.

STEP 10. Check whether the DTC is reset.
Q: Is DTC C2001 set?

YES : Replace the hydraulic unit (incorporates in

ASC-ECU).(Refer to

P.35C-272

.) Then go to Step 11.

NO : Intermittent malfunction. (Refer to GROUP 00

− How

to Cope with Intermittent Malfunction

P.00-15

.)

STEP 11. Check whether the DTC is reset.
Q: Is DTC C2001 set?

YES : Return to Step 1.
NO : The procedure is complete.

ACX00671AE

No continuity

Continuity

4 mm (0.16 in)

DIAGNOSIS

TSB Revision

ACTIVE SKID CONTROL SYSTEM (ASC)

35C-140

DTC C1000: Abnormality in stoplight switch circuit

CAUTION

• If there is any problem in the CAN bus lines, an incor-

rect diagnostic trouble code may be set. Prior to this
diagnosis, diagnose the CAN bus lines.

• Whenever the ECU is replaced, ensure that the CAN

bus lines are normal.

• When the hydraulic unit (integrated with ASC-ECU) is

replaced, always perform the calibration of steering
wheel sensor, G and yaw rate sensor, brake fluid pres-
sure sensor, cut valve, and inlet valve.(Refer to

P.35C-266

,

P.35C-267

,

P.35C-268

, and

P.35C-269

.)

.

CIRCUIT OPERATION

ETACS-ECU sends the ON signal generated when the brake
pedal is depressed and OFF signal generated when the pedal
is released to ASC-ECU via CAN bus lines.

.

DTC SET CONDITIONS

This diagnostic trouble code is set in the following case.

• The vehicle has run for a long time with the stoplight switch

turned ON.

• The OFF status of the stoplight switch does not match the

vehicle behavior.

.

PROBABLE CAUSES

• Improper adjustment of stoplight switch installation position

• Malfunction of the stoplight switch

• Malfunction of the stoplight

• Damaged wiring harness and connectors

• Malfunction of ETACS-ECU

• Malfunction of the ASC-ECU

AC708950

Connectors: C-43, C-47, C-48

AI

C-43 (B)

C-47

C-48

AC708972AL

Connectors: C-304, C-312

C-304

C-312

ETACS-ECU

DIAGNOSIS

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ACTIVE SKID CONTROL SYSTEM (ASC)

35C-141

DIAGNOSIS

Required Special Tools:

• MB991958 Scan Tool (M.U.T.-III Sub Assembly)

• MB991824: Vehicle Communication Interface (V.C.I.)

• MB991827 M.U.T.-III USB Cable

• MB991910 M.U.T.-III Main Harness A

STEP 1. Using scan tool MB991958, diagnose the CAN bus
lines.
Using scan tool MB991958, diagnose the CAN bus lines.
Q: Is the check result normal?

YES : Go to Step 3.
NO : Repair the CAN bus lines. (Refer to GROUP 54C

−

Troubleshooting

P.54C-14

.) After repairing the CAN

bus line, go to Step 2.

STEP 2. DTC recheck after repairing the CAN bus line
Q: Is DTC C1000 set?

YES : Go to Step 3.
NO : This diagnosis is complete.

STEP 3. Battery check
Refer to GROUP 54A

− Battery Test

P.54A-9

.

Q: Is the battery in good condition?

YES : Go to Step 4.
NO : Charge or replace the battery, and the go to Step 16.

STEP 4. Stoplight operation check
Check that the stoplight is turned "ON" when the brake pedal is
depressed, and that the stoplight is turned "OFF" when the
brake pedal is released.

OK:

When the brake pedal is released: OFF
When the brake pedal is depressed: ON

Q: Is the check result normal?

YES : Go to Step 17.
NO : Go to Step 5.

STEP 5. Check for stoplight switch installation
Refer to GROUP 35A

− On-vehicle Service

P.35A-12

.

Q: Is the check result normal?

YES : Go to Step 6.
NO : Install the stoplight switch correctly. (Refer to GROUP

35A

− On-vehicle Service

P.35A-12

.) Then, go to Step

19.

DIAGNOSIS

TSB Revision

ACTIVE SKID CONTROL SYSTEM (ASC)

35C-142

STEP 6. Stoplight switch continuity check
(1) Remove the stoplight switch. (Refer to GROUP 35A

− Brake

Pedal

P.35A-25

.)

(2) Connect the circuit tester (

Ω range) to the stoplight switch

connector terminal Nos. 1 and 2.

(3) When continuity does not exist with the plunger pressed

from the outer case end face by the dimension shown in the
figure, and when continuity exists with the plunger released,
the switch is in good condition.

Q: Is the check result normal?

YES : Go to Step 7.
NO : Replace the stoplight switch. (Refer to GROUP 35A

−

Brake Pedal

P.35A-25

.) Then go to Step 19.

STEP 7. Check for diagnostic trouble codes of other
systems
Check that no DTC is set by the rear combination light. (Refer
to GROUP 54A

− Rear Combination Light, Diagnostic Trouble

Code Chart

P.54A-196

.)

Q: Is the check result normal?

YES : Go to Step 8.
NO : Check whether the combination meter-related DTC is

set. (Refer to GROUP 54A

− Rear Combination Light,

Diagnostic Trouble Code Chart

P.54A-196

.) Then go

to Step 19.

STEP 8. ETACS-ECU fuse No.2 check
Q: Is the check result normal?

YES : Go to Step 14.
NO : Go to Step 9.

ACX00671AE

No continuity

Continuity

4 mm (0.16 in)