1998 SSANGYONG MUSSO Workshop Repair Manual

2A-2 SUSPENSION DIAGNOSIS
ApplicationDescription
4.75 - 5.25Power Voltage (V)
Axle Vertical
Acceleration
Sensor
(Wheel G
Sensor)Less than 10
Consuming Current (mA)
Less than 2.0 Output Current (mA)
Operating Characteristics
Type Damping
Force
Switching
Actuator3-stage Rotary Step Motor Type
Voltage Rating (V)
DC12
Current Rating (A)
Less than 2.5
Current Time (mS) 95 - 105
4.75 - 5.25Power Voltage (V)
Body
Vertical and
Lateral
Acceleration
Sensor
Less than 10 Consuming Current (mA)
Less than 2.0
Output Current (mA)
Operating Characteristics
Output Voltage
0.752.5 4.25
-1.5g
1g 3.5g
Acceleration
(Vertical Acceleration Sensor)
Output Voltage
0.752.5 4.25
-1g
0g 1g
Acceleration
(Lateral Acceleration Sensor)
Output Voltage
0.752.5 4.25
-9g
1g
11 g
Acceleration
GENERAL SPECIFICATIONS (Cont'd)

SUSPENSION DIAGNOSIS 2A-3
DIAGNOSIS
GENERAL DIAGNOSIS
Checks
Loosened Mountings
Damaged or Worn wheel Bearing
Damaged Shock Absorber
Damaged TireAction
Retightening
Replace
Replace
Replace
Abnormal Noises
Checks
Broken Stabilizer Bar
Faulty Shock AbsorberAction
Replace
Replace
Vehicle Rolling
Checks
Over Inflated Tire
Faulty Shock Absorber
Loosened wheel Nut
Bent or Broken Coil Spring
Damaged Tire
Worn BushingAction
Pressure Adjustment
Replace
Tighten as Specified
Replace
Replace
Replace
Poor Riding
Problems in the steering, the suspension, the tires, and
the wheels involve several systems. Consider all systems
when you diagnose a complaint. Some problems, such
as abnormal or excessive tire wear and scuffed tires,
may by the result of hard driving. Always road test thevehicle first. If possible, do this road test with the
customer.
Proceed with the following preliminary checks. Correct
any substandard conditions.
Checks
Incorrect Wheel Alignment
Excessive Resistance of Lower Arm Ball Joint
Insufficient Tire Pressure
Faulty Power Steering
Action
Repair
Replace
Adjust
Repair or Replace
Hard Steering
Checks
Deformed Arm Assembly
Worn Bushing
Bent or Broken Coil Spring
Difference Between L/H & R/H HeightsAction
Replace
Replace
Replace
Adjust
Vehicle Pulls to Right or Left

2A-4 SUSPENSION DIAGNOSIS
Checks
Worn or Broken Coil SpringChecks
Incorrect Front wheel Alignment
Worn or Loosened Lower Arm Bushing
Action
Replace
Repair or Replace
Steering Instability
Action
Replace
Vehicle Bottoming

SUSPENSION DIAGNOSIS 2A-5
INPUT & OUTPUT DEVICES AND DAMPING FORCE
CONTROL LOGIC
INPUT & OUTPUT DEVICES
Damping force of shock absorber will rotate shock absorber control rod in 3 modes by driving actuator on the upper
shock absorber when signaled from ECS.
Rotary valve in the shock absorber will control hydraulic flow according to rotation of control rod to adjust damping
force of shock absorber in SOFT«MEDIUM«HARD.
SYSTEM LAYOUT
1 ECS (ECU)
2 Body Vertical Acceleration Sensor (Vertical
Sensor)
3 Body Lateral Acceleration Sensor (Lateral
Sensor)
Speed Sensor
Axle Vertical Acceleration Sensor
(Wheel G Sensor)
Stop Lamp Switch
Body Vertical Acceleration Sensor
(Vertical Sensor)
ECS Switch
Indicator Lamp
Actuator
Shock Absorber
Self-Diagnosis Connector
Damping Force Adjustment
ECS
(ECU)
Body Lateral Acceleration Sensor
(Lateral Sensor)
4 ECS Mode Switch
5 Stop Lamp Switch
6 Axle Vertical Acceleration Sensor (Wheel G
Sensor)
7 Mode Actuator

2A-6 SUSPENSION DIAGNOSIS
DAMPING FORCE CONTROL LOGIC
Control Logic that applies on damping force variable suspension is comprised of road sensing driving comfort control
logic to increase driving comfort and vehicle speed sensing control logic, anti-roll control logic and anti-dive control
logic to secure control safety.
LogicSensor
Road Sensing Driving Comfort Control LogicSpeedVertical
Sensor (2.5g)Lateral
Sensor (1g)Axle
Acceleration
Sensor (10g)Brake
Anti-bounce Control Logic
Anti-roll Control Logic
Anti-dive Control Logic
Vehicle Speed Sensing Control Logic
NORMAL CONTROL
Initial Stage
When ignition switch is "ON", system initialization will be performed for approx. 3 seconds. During this time, warning
lamp will stay ON and damping force will be switched to Hard status. After 3 seconds, warning lamp will turn off and
normal control status will be restored.
Normal Damping Force Control Establishment
Damping force will have Soft®Medium®Hard status in AUTO mode and Medium®Hard status in SPORT mode.
When double control items are satisfied at the same time it will be Hard®Medium®Soft in order.
Normal Damping Force Control Release
Control mode release will be "Hard®Medium®Soft"or "Medium®Soft". In case that returned from Hard status to
Medium status during control, it will be done after elapse of setting times. Returning from Medium status to Soft status
will be done immediately without delay.

SUSPENSION DIAGNOSIS 2A-7
SELF-DIAGNOSIS
ECS-ECU indicates ECS circuit defectives to the driver by flickering ECS indicator lamp in the meter cluster 0.5
second of interval if there are defectives.
Code
Body vertical
acceleration
sensor Defects
When sensor output
voltage is less than
0.5-4.5V, more than
4.5V. Judging Conditions01
0.9 - 1.1sec.Set TimeSensor Voltage
³2.0 ± 0.1V
³3.0 ± 0.1V
Release Conditions
0.9 - 1.1sec.Set Time
Body lateral
acceleration
sensorWhen sensor output
voltage is less than
0.55±0.15V, more than
4.45±0.1V. 02
0.9 - 1.1sec.
Sensor Voltage
³2.0 ± 0.1V
³3.0 ± 0.1V
0.9 - 1.1sec.
Stop anti-
bounce ride
control Remedy
Stop anti-roll
control
Axle vertical
acceleration
sensor (wheel G
sensor)When sensor output
voltage is less than
0.5-4.5V, more than
4.5V. 03
0.9 - 1.1sec.
Sensor Voltage
³2.0 ± 0.1V
³3.0 ± 0.1V
0.9 - 1.1sec.
Stop ride
control
Front actuatorCheck step motor
power supply detecting
circuit for open and
short.
check for relative
connectors. 04
0.4 - 0.6sec.
IGN+ SW.
OFF®
ONStop control
after returning
to the previ-
ous mode
Rear actuatorWhen defective detect-
ing circuit has detected
defectives during
output OFF. 05
0.4 - 0.6sec.IGN+ SW.
OFF®
ONStop control
after returning
to the previous
mode
ECU
When ECU does not
work normally. 06
0.4 - 0.6sec.Reset
Stop control
1. Turn the ignition switch ON and if ECS system is normal, ECS indicator lamp will turn on for 3 seconds and then go
off. However if defective, ECS indicator lamp will flicker in the interval of 0.5 second continuously.
2. Identify fault code with Scanner.

2A-8 SUSPENSION DIAGNOSIS
-
ACTUATOR INSPECTION
Output position of the actuator should be changed as below when battery voltage is applied between actuator
connector terminals.
Connector
terminalBattery VoltagePosition of The Actuator OutputRemark
1 (White)
-
2 (Black)OPEN
3 (Red)
+
1 (White)
+
2 (Black)
-
3 (Red)OPEN
1 (White)OPEN
2 (Black)
+
3 (Red)
SOFT Mode
MEDIUM Mode
HARD Mode

SUSPENSION DIAGNOSIS 2A-9
ECS CIRCUIT
SCHEMATIC AND ROUTING DIAGRAMS