MITSUBISHI ENDEAVOR 2004 Service Repair Manual

Fig. 2: Traction Control, Active Skid Control Function Outline

Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
SYSTEM CHECK SOUND When starting the engine, a thudding sound can sometimes be heard coming from
the engine compartment. This is a normal sound during the TCL/ASC self-check. TCL/ASC OPERATION SOUNDS AND SENSATIONS During normal operation, the TCL/ASC makes several sounds that may seem
unusual at first:
2004 Mitsubishi Endeavor LS
2004 BRAKES Traction Control, Active Skid Control System - Endeavor

A whining sound is caused by the TCL/ASC hydraulic unit motor. When pressure is applied to the brake pedal, the pulsation of the pedal causes a
scraping sound. When the brakes are applied firmly, the TCL/ASC operates, rapidly applying
and releasing the brakes many times per second. This repeated application and
release of braking forces can cause the suspension to make a thumping sound
and the tires to squeak.
SENSOR G AND YAW RATE SENSOR This sensor is mounted under the center console, and detects lateral acceleration,
longitudinal acceleration and steering angular velocity of the vehicle.
Fig. 3: Identifying G And Yaw Rate Sensor
2004 Mitsubishi Endeavor LS
2004 BRAKES Traction Control, Active Skid Control System - Endeavor

Courtesy of MITSUBISHI MOTOR SALES OF AMERICA
.
STEERING WHEEL SENSOR
This sensor is mounted behind the column switch, and detects the steering
wheel position. The steering wheel sensor has a self-diagnosis function and a memory
function. If the diagnosis function finds a trouble, it sends a DTC code to the
TCL/ASC-ECU. Then the ECU will illuminate the TCL/ASC indicator light.
Fig. 4: Identifying Steering Wheel Sensor

Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
TRACTION CONTROL OFF SWITCH
NOTE: For the details of the DTC codes, refer to DIAGNOSTIC
TROUBLE CODE CHART
.

2004 Mitsubishi Endeavor LS
2004 BRAKES Traction Control, Active Skid Control System - Endeavor

This switch is mounted on the left side of the instrument panel, and turns on and off
the system.
Fig. 5: Identifying Traction Control Off Switch

Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
TRACTION CONTROL OFF SWITCH POSITION AND THEIR RESPECTIVE CONTROL Fig. 6: Traction Control Off Switch Position And Respective Control Specifications

Courtes
y of MITSUBISHI MOTOR SALES OF AMERICA
.

2004 Mitsubishi Endeavor LS
2004 BRAKES Traction Control, Active Skid Control System - Endeavor

ACTUATOR HYDRAULIC UNIT The hydraulic unit includes a cut valve, suction valve and pressure switch for the
active skid control additionally, compared with the conventional hydraulic unit for
the ABS control. TRACTION CONTROL/ACTIVE SKID CONTROL SYSTEM OPERATION INDICATOR LIGHT AND TRACTION
CONTROL SYSTEM OFF INDICATOR LIGHT The Traction control/Active skid control system operation indicator light and
Traction control system OFF indicator light illuminate or flash under the conditions
below to inform the driver. TRACTION CONTROL/ACTIVE SKID CONTROL SYSTEM INDICATOR LIGHT
When the active skid control is active, the light flashes. When the traction control is active, the light flashes. When sensors related to traction control and active skid control are not
initialized, the li
ght flashes at a fre
quenc
y of once
per second.
NOTE:
The Traction control will activate when the system has
not been disabled by the traction control OFF switch,
and the vehicle speed has reached 4 - 9 mph (6 - 14
km/h). The traction control will deactivate when the front wheel
speed (both wheels) have decreased to 1 - 4 mph (2 - 6
km/h) for one second or more (four seconds or more if
the system is controlling the engine output). The Active skid control will be activated when the
vehicle speed exceeds 12 mph (20 km/h). The Active skid control will deactivate when the vehicle
speed has decreased to 9 mph (15 km/h) or lower.
NOTE: For the internal hydraulic circuit of the hydraulic unit, refer
to ACTIVE SKID CONTROL SYSTEM OPERATION
.

2004 Mitsubishi Endeavor LS
2004 BRAKES Traction Control, Active Skid Control System - Endeavor

When there is a failure in the traction control/active skid control system, the
light illuminates.
TRACTION CONTROL SYSTEM OFF INDICATOR LIGHT
When the traction control is inactive, the light illuminates. When the traction control/active skid control system is defective, the light
flashes at a frequency of once per second.
INDICATOR LIGHT OPERATION PATTERN Fig. 7: Traction Control System Off Indicator Light Specification

Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
TCL/ASC-ECU
2004 Mitsubishi Endeavor LS
2004 BRAKES Traction Control, Active Skid Control System - Endeavor

The ECU incorporates the ABS-ECU, active skid control-ECU, and traction
control-ECU. The integral design allows joint operation of the TCL/ASC-ECU with
the ABS and coordinated control of the driving force and braking force. SYSTEM CONFIGURATION The Traction Control and Active Skid Control (TCL/ASC) System is a system that
adds a yaw rate sensor, a steering wheel sensor and master cylinder pressure sensor
(incorporated in hydraulic unit) to the ABS system. OVERVIEW OF CONTROL The TCL/ASC-ECU detects vehicle movement based on information from various
sensors and calculates a model of ideal vehicle movement. After comparing actual
and ideal movements, it acts to bring the actual vehicle movement closer to the
ideal model by controlling specific wheel brake force and governing engine output.
It restrains under-steering and over-steering through a corrective yaw moment, as
explained on the following pages. EXAMPLE OF ACTIVE SKID CONTROL OPERATION The Active Skid Control manages the vehicle attitude by creating a yaw moment
from altering the balance between the cornering force and each wheel's braking
mechanism.
For example, on a slippery surface, if the vehicle tends to be under-steered contrary
to the driver's intention, a yaw moment (a rotational moment) is created to restrain
the under-steering by increasing the rear-inside braking force. On the other hand,
when the vehicle tends to be over-steered, a yaw moment (a restorative moment) is
created to restrain the over-steering by increasing the front-outside braking force.
Furthermore, when it is determined that the vehicle is over-speeding, safe and stable
cornerin
g is enabled b
y deceleration from restrictin
g en
gine out
put.

2004 Mitsubishi Endeavor LS
2004 BRAKES Traction Control, Active Skid Control System - Endeavor

Fig. 8: Identifying Example Of Active Skid Control Operation

Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
EXAMPLE OF THE EFFECT OF CONTROL
2004 Mitsubishi Endeavor LS
2004 BRAKES Traction Control, Active Skid Control System - Endeavor

Fig. 9: Identifying Examples Of The Effect Of Control

Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
JOINT CONTROL The Active Skid Control transmits data necessary for control of the ABS and the
Traction Control, performing joint control.
2004 Mitsubishi Endeavor LS
2004 BRAKES Traction Control, Active Skid Control System - Endeavor

Fig. 10: Identifying Joint Control Specification
s
Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
EXAMPLE OF OPERATION OF TRACTION CONTROL The Traction Control prevents drive force loss during slipping of the drive wheels
by automatically applying the brakes and sending engine torque reduction signal to
the PCM when the drive wheels slip or when driving on partly low-friction
surfaces. FAIL-SAFE AND DIAGNOSTIC FUNCTIONS The TCL/ASC-ECU regularly monitors input and out put signals. If an error is
detected in the system, the ECU sends a fail signal and the TCL/ASC indicator light
is illuminated or blinks. Various controls are processed depending on the cause of
malfunction as shown below. When the ABS system fails, the TCL/ASC system is
also suspended. However, when the TCL/ASC system fails, no other systems are
suspended. The appropriate indicator lights are illuminated/flashed.
The TCL/ASC-ECU includes the following functions to make system inspection
easier.
Diagnostic trouble code Display Data list Actuator test
All of the above operations can be carried out using scan tool MB991958.
ACTIVE SKID CONTROL SYSTEM OPERATION The TCL/ASC-ECU receives information from the PCM, the steering sensor, the G
and yaw-rate sensor and the wheel speed sensor. If the ECU determines that the
vehicle is tending to oversteer or understeer, it sends signals to the active skid
control system valves and the ABS solenoid valves to increase the fluid pressure to
the wheels.
The system closes the cut valve to shut the fluid channel to the suction valve, and
activates the
pum
p motor. The brake fluid, which is
pum
ped throu
gh the h
ydraulic

2004 Mitsubishi Endeavor LS
2004 BRAKES Traction Control, Active Skid Control System - Endeavor